SlideShare a Scribd company logo
1 of 9
Download to read offline
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
DOI : 10.5121/jgraphoc.2012.4401 1
On the Odd Gracefulness of Cyclic Snakes With
Pendant Edges
E. M. Badr
Department of Scientific Computing, Faculty of Computer Science and Informatics,
Benha University, Benha, Egypt
badrgraph@gmail.com
ABSTRACT
Graceful and odd gracefulness of a graph are two entirely different concepts. A graph may posses one or
both of these or neither. We present four new families of odd graceful graphs. In particular we show an odd
graceful labeling of the linear 4 1
kC snake mK
βˆ’ e and therefore we introduce the odd graceful labeling of
4 1
kC snake mK
βˆ’ e ( for the general case ). We prove that the subdivision of linear 3
kC snake
βˆ’ is odd
graceful. We also prove that the subdivision of linear 3
kC snake
βˆ’ with m-pendant edges is odd graceful.
Finally, we present an odd graceful labeling of the crown graph 1
n
P mK
e .
KEYWORDS
Graph theory, odd graceful labeling, path, cyclic snakes, pendant edges.
1. INTRODUCTION
The graphs considered here will be finite, undirected and simple. The symbols V(G) and E(G)
will denote the vertex set and edge set of a graph G respectively. p and q denote the number of
vertices and edges of G respectively.
A graph G of size q is odd-graceful, if there is an injection Ο† from V(G) to {0, 1, 2, …, 2q-1}
such that, when each edge xy is assigned the label or weight |Ο† (x) - Ο† (y)|, the resulting edge
labels are {1, 3, 5, …, 2q-1}. This definition was introduced in 1991 by Gnanajothi [1] who
proved that the class of odd graceful graphs lies between the class of graphs with Ξ±-labelings and
the class of bipartite graphs. We denote the crown graphs ( the graphs obtained by joining a single
pendant edge to each vertex of Cn ) by 1
n
C K , therefore the crown graphs (the graphs obtained
by joining m-pendant edges to each vertex of Cn ) by 1
n
C mK . Gnanajothi [1] proved that
1
n
C K is odd graceful if n is even. Badr et al [2] proved that 1
n
C mK is odd graceful if n is
even.
A n
kC snake
βˆ’ is a connected graph with k blocks, each of the blocks is isomorphic to the cycle
Cn, such that the block-cut-vertex graph is a path. Following [3], by a block-cut-vertex graph of a
graph G we mean the graph whose vertices are the blocks and cut-vertices of G where two
vertices are adjacent if and only if one vertex is a block and the other is a cut-vertex belonging to
The block. We also call a n
kC snake
βˆ’ as a cyclic snake. This graph was first introduced by
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
2
Barrientos [4], as generalization of the concept of triangular snake introduced by Rosa [5].
Let G be a n
kC snake
βˆ’ with k β‰₯ 2. Let u1, u2, . . ., uk-1 be the consecutive cut-vertices of G. Let
di be the distance between vi and vi+1 in G, 1 2
i k
≀ ≀ βˆ’ . The string (d1, d2, … , dk-2 ) of integers,
characterizes the graph G in the class of n-cyclic snakes. The n
kC snake
βˆ’ contains q= nk edges and
p = ( n - 1 )k + 1 vertices. Among these vertices, k – 1 vertices have degree 4 and the other
vertices of degree 2.
Now, let us consider a 4
kC snake
βˆ’ . The first non trivial quadrilateral snake is 4
2C snake
βˆ’ as
shown in Figure 1. Two different 4
kC snake
βˆ’ can be constructed from a 4
( 1)
k C snake
βˆ’ βˆ’ .
Figure 1. 2C4-snake with a cut-vertex
Example 1.1 We can construct two different 4
3C snake
βˆ’ from a 4
2C snake
βˆ’ , the first is
with string ( 1 ) ( Figure 2a ) and the second is with string ( 2 ) ( Figure 2b ) .
a) b)
Figure 2. 3C4-snakes with string 1 and string 2 respectively.
Badr and Mousa [6] proved that kC4- snake, linear kCn- snake , even kC8 - snake and even kC12-
snakes are odd graceful.
We denote the crown snakes ( the graphs obtained by joining m-pendant edges to each vertex of
kCn-snake ) by 1
n
kC snake mK
βˆ’ e .
Definition 1.2 The kCn-snake is called linear, if the block-cut-vertex graph of kCn-snake has the
property that the distance between any two consecutive cut-vertices is
2
n
ο£― ο£Ί
ο£― ο£Ί
ο£° ο£»
.
In this work we present four new families of odd graceful graphs. In particular we show that an
odd graceful labeling of the linear 4 1
kC snake mK
βˆ’ e and therefore we introduce the odd
graceful labeling of 4 1
kC snake mK
βˆ’ e ( for the general case ). We prove that the subdivision of
linear 3
kC snake
βˆ’ is odd graceful. We also prove that the subdivision of linear 3
kC snake
βˆ’ with
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
3
m-pendant edges is odd graceful. Finally, we present an odd graceful labeling of the crown graph
1
n
P mK
e .
2 The Results
Theorem 2.1 The linear 4 1
kC snake mK
βˆ’ e is odd graceful.
Proof. Let G = linear 4 1
kC snake mK
βˆ’ e with the vertices wi , uj and vj where i = 0,1, 2,
…, k, j = 0,1, 2, …, k-1. In order to get the linear 4 1
kC snake mK
βˆ’ e , we add m-pendant edges
wi
l
, uj
l
and vj
l
to each vertex of wi , uj and vj respectively such that l=1,2, …, m. Now, the graph
4 1
kC snake mK
βˆ’ e has the vertices wi , uj , vj , wi
l
, uj
l
and vj
l
such that i = 0,1, 2, …, k, j = 0,1,
2, …, k-1 and l = 1, 2, …, m.
Figure 3. 4 1
3 2
C snake K
βˆ’ e is odd graceful
Clearly the linear 4 1
kC snake mK
βˆ’ e has p = (3k+1)(m+1) vertices and q = 4k+m(3k+1) edges.
Let us consider the following numbering Ο† of the vertices of the graph G :
Ο† (wi) = 2i(m + 1) i = 0, 1, 2, …, k.
Ο† (ui) = 2q – 2i(m + 1 ) - 1 i = 0, 1, 2, …, k.
Ο† (vi) = 2q – 4k(m + 1 ) – 2i - 1 i = 0, 1, 2, …, k.
Ο† ( wl
0 ) = 2l – 1, l = 1, 2, …, m.
Ο† (wi
l
) = 2(q-l + m - i(m+1) +1 i = 1, 2, …, k.
Ο† (ui
l
) = 2 ( l+ i( m + 1) ) i = 0, 1, 2, …, k-1 , l = 1, 2, …, m.
Ο† (vi
l
) = 4( q – 2k( m + 1) ) – 2( l + 1 + i( m + 3) ) i = 0, 1, 2, …, k-1 , l = 1, 2, …, m.
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
4
(a)
{0 0 1 1
0 0 1
0 1 1 1
0 1
1
( ) max 2 ( 1), 2 - 2 ( 1 ) - 1, 2 - 1,
max max max
2 - 4 ( 1 ) - 2 - 1, 2( - - ( 1) 1, 2 ( ( 1) ),
max max max
4(
max
v V i k i k l m
i k i k
i k l m l m
i k
l m
Max v i m q i m l
q k m i q l m i m l i m
Ο†
∈ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀
≀ ≀ ≀ ≀ βˆ’
≀ ≀ βˆ’ ≀ ≀ ≀ ≀
≀ ≀ βˆ’
≀ ≀
= + +
+ + + + + +
- 2 ( 1) ) - 2( 1 ( 3) )
q k m l i m
ο£Ό
+ + + + ο£½
ο£Ύ
= 2q – 1, the maximum value of all odds. .
Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}.
(b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}.
(c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1,
2q-1].
The range of | ( ) ( ) | {2 4 ( 1) 2 ( 2) 1: 0,1,2,..., 1}
i i
v w q k m i m i k
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ + βˆ’ = βˆ’
= { 2q - 4k(m+1) - 1, …, 2q -4k(m+1) – 2m - 5, … , 2q -6km -8k +2(m+2) - 1 }
i+1
The range of | ( ) ( ) | {2 4 ( 1) 2 ( 2) 2 3: 0,1,2,3,..., 1}
i
v w q k m i m m i k
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ + βˆ’ βˆ’ = βˆ’
= { 2q – 4k(m+1)-8k+1, 2q-4k(m+1)-4m-7, …, 2q-6km-8k+1}
i
T he range of | ( ) ( ) | {2 4 ( 1) 1 : 0,1, 2, 3,..., 1}
i
u w q i m i k
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ = βˆ’
= { 2q-1, 2q-4(m+1) - 1, …, 2q-4(k-1)(m+1) - 1}
i
The range of | ( ) ( ) | {2 4 ( 1) 2 3: 0,1,2,3,..., 1}
i
u w q i m m i k
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ βˆ’ = βˆ’
= { 2q-2m-3, 2q-6m-7 …, 2q-4(k-1)(m+1) – 2m-3}
l
0 0
The range of | ( ) ( ) | {2 1: 1,2,3,..., }
w w l l m
Ο† Ο†
βˆ’ = βˆ’ = = { 1, 3, …, 2m -1}
l
i
The range of | ( ) ( ) | {2( 2 ( 1)) 1: 1,2,3,..., , 1,2,3,..., }
i
w w q l m i m i k l m
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ + + = =
= { 2( q –l – m) – 3, 2( q – l – 3m) – 7, …, 2(q-l+m-2k(m+1))+1}
l
i
The range of | ( ) ( ) | {2( 2 ( 1) 1: 0,1,2,3,..., 1; 1,2,3,..., }
i
u u q l i m i k l m
Ο† Ο†
βˆ’ = βˆ’ βˆ’ + βˆ’ = βˆ’ =
= { 2(q-l)-1, 2(q-l-2(m+1)-1, …, 2(q-l-2(k-1)(m+1)-1}
l
i
The range of | ( ) ( )| {2( 2 ( 1) ( 2)) 1:0 1;1 }
i
v v q k m l i m i k l m
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ βˆ’ + βˆ’ ≀ ≀ βˆ’ ≀ ≀ = { 2(q-2k(m+1)-l)-1,
2(q-2k(m+1)-l-(m+2))-1, …, 2[q-2k(m+1)-l-(k-1)(m+2)]-1}
Hence {| ( ) ( ) |: } {1,3,5,...,2 1}
u v uv E q
Ο† Ο†
βˆ’ ∈ = βˆ’ so that the graph G is odd graceful.β– 
Theorem 2.2 The 4 1
kC snake mK
βˆ’ e is odd graceful.
Proof. Let G = 4 1
kC snake mK
βˆ’ e . The graph G obtained by joining m-pendant edges to each
vertex of 4
kC snake
βˆ’ . Now, we are running the following steps sequentially in order to prove
the Theorem.
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
5
Figure 4 . 4 1
4 2
C K snake
βˆ’
e is odd graceful
Step 1 .
Since 4
kC snake
βˆ’ is a bipartite graph so it has one partite set has black vertices and the other has
white vertices as shown in Figure 4.
Put black vertices in a string, ordered by diagonals from left to right and inside each diagonal
from bottom to top, assign to them from an arithmetic progression of difference 2, which first
term is zero, counting until the last black vertex has been numbered. Similarly, put the white
vertices on a string, ordered for diagonals from left to right and inside each diagonal from top to
bottom. Starting with the first diagonal assign numbers from an arithmetic progression of
difference 4, which first term is 2q-1 where q is the size of G, while to move to another diagonal
we use an arithmetic progression of difference 2 but the arithmetic progression of difference 4 is
used inside each diagonal, continuing until the last white vertex has been numbered.
Step 2 .
In this step, we are labeling the vertices of m-pendant edges which contact with black diagonals,
from left to right and inside each black diagonal from bottom to top, assign to them from an
arithmetic progression of difference 2, which first term is one, when to move to a new vertex of
the block diagonal, the first vertex of m-pendant edges is labeled by an arithmetic progression of
difference 4, but the arithmetic progression of difference 2 has been used with the remain ( m-1 )
vertices of m-pendant edges. We move from a vertex to another of the black diagonals until the
last black vertex.
Step 3 .
Finally, we are labeling the vertices of m-pendant edges which contact with the white diagonals,
from right to left an inside each white diagonal from bottom to top, assign to them from an
arithmetic progression of difference 2, which first term is z such that z = y + 2 where y is the last
vertex labeling of the black diagonals, when to move to a new vertex of the white diagonal, the
first vertex of m-pendant edges is labeled by an arithmetic progression of difference 6, but the
arithmetic progression of difference 2 has been used with the remain ( m-1 ) vertices of m-
pendant edges. When to move to another diagonal we use an arithmetic progression of difference
4 but the arithmetic progression of difference 2 has been used with the remain ( m-1 ) vertices of
m-pendant edges. We move from a vertex to another of the white diagonals until the last white
vertex. We have the complete proof of the Theorem by running the above steps. β– 
Theorem 2.3 The subdivision of linear 3
kC snake
βˆ’ is odd graceful.
Proof : We prove that the subdivision of graph S ( kC3-snake ) ( obtained by subdividing every
edge of kC3-snake exactly once ) is odd graceful.
0
2
4
6
8
1 0
1 3
7 9
1 3 1 5
1 9 2 1
2 5 2 7
3 1 3 3
8 3
7 9
7 7
7 3
6 9
6 7
6 3
1 2 1 4
2 0 2 2
2 6 2 8
3 4 3 6
4 2 4 4
4 8 5 0
5 6 5 8
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
6
Let u0, u1, . . . , uk, v0, v1, . . . , vk-1 be the vertices of the kC3-snake . Let yi be the newly added
vertex between ui and ui+1 where i = 0, 1, . . . , k-1 but wi be the newly added vertex between uj,vj
and vj ,uj+1 ( from left to right ) such that i = 0,1, . . . ,2k-1 and j= 0,1, . . . , k-1 (Figure 5).
Figure 5. S ( 3C3-snake ) is odd graceful
Clearly S ( kC3-snake ) has p = ( n + 2 )k + 1 vertices and q = 2nk edges. Let us consider the
following numbering Ο† of the vertices of S ( kC3-snake ):
Ο† ( ui ) = 4i , where i = 0, 1, 2, . . . , k.
Ο† ( vi ) = 4i + 2 , where i = 0, 1, 2, . . . , k – 1.
Ο† ( wi ) = 2q -2i -1 , where i = 0, 1, 2, . . . , 2k – 1.
Ο† ( yi ) = 2q - 8k – 4i - 1 , where i = 0, 1, 2, . . . , k – 1.
(a)
{0 0 1 0 2 1 0 1
( ) max 4 , 4 2, 2 - 2 -1, 2 -8 - 4 -1
v V
Max v i i q i q k i
max max max max
ΞΉ ΞΊ ΞΉ ΞΊ ΞΉ ΞΊ ΞΉ ΞΊ
Ο†
∈ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀ βˆ’ ≀ ≀ βˆ’
ο£Ό
= + ο£½
ο£Ύ
= 2q – 1, the maximum value of all odds. .
Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}.
(b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}.
(c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1,
2q-1]. Let r be the number of block which has the vertex vi or ui where i = 1, 2, . . . , k.
The range of | ( ) ( ) | {2 8 8 1: 0,1,2,..., 1}
i i
u y q k i i k
Ο† Ο†
βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’
= { 2q – 8k -1, …, 2q – 8k- 9, … , 2q -16k + 7 }
1
The range of | ( ) ( ) | {2 8 8 5: 0,1,2,..., 1}
i i
y u q k i i k
Ο† Ο† +
βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’
= { 2q – 8k -5, …, 2q – 8k - 13, … , 2q -16k + 3 }
1
The range of | ( ) ( ) | {2 6 2 1: 0,1,2,..., }
i i r
u w q i r i k
Ο† Ο† + βˆ’
βˆ’ = βˆ’ βˆ’ + =
= { 2q – 1, …, 2q – 7, … , 2q - 8k + 1 }
The range of | ( ) ( ) | {2 6 2 3: 0,1,2,..., 1}
i i r
v w q i r i k
Ο† Ο† +
βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’
= { 2q – 5, …, 2q – 13, … , 2q - 8k + 3 }
1
The range of | ( ) ( ) | {2 6 2 1: 0,1,2,..., 1}
i i r
v w q i r i k
Ο† Ο† + βˆ’
βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’
= { 2q – 3, …, 2q – 11, … , 2q - 8k + 5 }
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
7
Hence {| ( ) ( ) |: } {1,3,5,...,2 1}
u v uv E q
Ο† Ο†
βˆ’ ∈ = βˆ’ so that the graph S ( kC3-snake ) is odd graceful.
β– 
Theorem 2.4 The subdivision of linear 3
kC snake
βˆ’ with m-pendant edges is odd graceful.
Proof. We prove that the linear 3 1
( )
S kC snake mK
βˆ’ e is odd graceful , where 3
( )
S kC snake
βˆ’ is
obtained by subdividing every edge of kC3-snake exactly once and mK1 are m-pendant edges
which join to every vertex of the graph 3
( )
S kC snake
βˆ’ .
Let u1, u2, . . . , uk+1, w1, w2, . . . , vk be the vertices of the kC3-snake . Let yi be the newly added
vertex between ui and ui+1 where i = 1, . . . , k while vi be the newly added vertex between ui,wi
where i = 1, . . . , k. Finally zi be the newly added vertex between wi ,ui+1 wher i = 1, 2, . . . ,k. In
order to get the graph G = linear 3 1
( )
S kC snake mK
βˆ’ e , we add m-pendant edges l
i
u , l
i
y , l
i
v ,
l
i
w and l
i
z to each vertex of i
u , i
y , i
v , i
w and i
z respectively.
Clearly the graph G has p = (5k+1)m vertices and q = (5m + 6) (k - 1) + m edges.
Define : ( ) {0,1,2,...,2 1}
V G q
Ο• β†’ βˆ’ as follows:
( ) 4( 1)( 1) 1 1
i
u m i i k
Ο† = + βˆ’ ≀ ≀ +
( ) 2 (2 4) 2 3 1
i
v q m i m i k
Ο† = βˆ’ + + + ≀ ≀
( ) 2( 1)(2 1) 1
i
w m i i k
Ο† = + βˆ’ ≀ ≀
( ) 4( 1)( ) 4 3 1
i
y m k i m i k
Ο† = + βˆ’ + + ≀ ≀
( ) 2 2 ( 2) 1 1
i
z q i m i k
Ο† = βˆ’ + + ≀ ≀
( ) 4 ( 1) 2( 1) 1 ; 1
l
i
v i m l m i k l m
Ο† = + + βˆ’ βˆ’ ≀ ≀ ≀ ≀
( ) 2 2 ( 2) 2( ) 3 1 ; 1
l
i
w q i m l m i k l m
Ο† = βˆ’ + βˆ’ βˆ’ + ≀ ≀ ≀ ≀
( ) 4 ( 1) 2( 1) 1 ; 1
l
i
z i m k m i k l m
Ο† = + + βˆ’ βˆ’ ≀ ≀ ≀ ≀
1
( ) 2 2 (2 4) 2 2 1
l
y q l m k m l m
Ο† = βˆ’ βˆ’ + βˆ’ βˆ’ ≀ ≀
( ) 2 ( 1) 2 ( 1) ( ); 2,3,4,..., ( ),1
l
i
y q i m l m k k odd i n i even l m
Ο† = βˆ’ + βˆ’ + + = ≀ ≀
( ) 2 ( 1) 2 ( 1) 2 ( ); 2,3,4,..., ( ),1
l
i
y q i m l m k k odd i n i odd l m
Ο† = βˆ’ + βˆ’ + + + = ≀ ≀
( ) 2 ( 1) 2 ( 1) 2 ( ); 2,3,4,..., ( ),1
l
i
y q i m l m k k even i n i even l m
Ο† = βˆ’ + βˆ’ + + + = ≀ ≀
( ) 2 ( 1) 2 ( 1) ( ); 2,3,4,..., ( ),1
l
i
y q i m l m k k even i n i odd l m
Ο† = βˆ’ + βˆ’ + + = ≀ ≀
1
( ) 2 1 1
l
u l l m
Ο† = + ≀ ≀
( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1
l
i
u q i m l m k m k even i n n even l m
Ο† = + + βˆ’ βˆ’ + βˆ’ βˆ’ = βˆ’ ≀ ≀
( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1
l
i
u q i m l m k m k even i n n odd l m
Ο† = + + βˆ’ βˆ’ + βˆ’ + = βˆ’ ≀ ≀
( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1
l
i
u q i m l m k m k odd i n n even l m
Ο† = + + βˆ’ βˆ’ + βˆ’ + = βˆ’ ≀ ≀
( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1
l
i
u q i m l m k m k odd i n n odd l m
Ο† = + + βˆ’ βˆ’ + βˆ’ βˆ’ = βˆ’ ≀ ≀
( ) 2 2 (2 4) 2 5 1
l
n
u q l m n m l m
Ο† = βˆ’ βˆ’ + + + ≀ ≀
Then clearly the mapping Ο† is an odd graceful labeling.β– 
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
8
Theorem 2.5 The crown graph 1
n
P mK
e is odd graceful.
Proof. We can see the crown graph G = 1
n
P mK as the path Pn which has the vertices ( v1, v2,
v3 …, vn) such that each vertex vi adjacent to m pendent edges vi
l
where i = 1, 2, 3, . . ., n and l = 1,
2, 3, . . ., m.
Let us consider the following numbering Ο† of the vertices of G.
Ο† (vi) = (m + 1 )( i – 1 ), ( i odd ), i = 1, 2, …, n.
Ο† (vi) = 2q – (m + 1 )( i – 1 ) - m, ( i even ), i = 1, 2, …, n.
Ο† (vi
k
) = 2q – (m + 1 )( i – 1 ) - 2l + 1, ( i odd ), i = 1, 2, …, n, l = 1, 2, …, m.
Ο† (vi
k
) = (m+1)(i+1)+2k-(m+1) , ( i even ), i = 1, 2, …, n, l = 1, 2, …, m.
(a)
{ 1 ,i odd
i odd i even
1 1 1
1 ,i even
1
Max ( ) max ( + 1 )( - 1 ), 2 - ( + 1 )( - 1 ) - , 2 - ( + 1 )( - 1 ) - 2 + 1,
max max max
2 - ( + 1 )( - 2 ) + 2
max
l m
v V i n i n i n
l m
i n
v m i q m i m q m i l
q m i l
Ο†
≀ ≀
∈ ≀ ≀ ≀ ≀ ≀ ≀
≀ ≀
≀ ≀
=
ο£Ό
ο£½
ο£Ύ
= 2q – 1, the maximum value of all odds. .
Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}.
(b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}.
(c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1,
2q-1].
1
The range of | ( ) ( ) | {2 2 ( 1) : 1,2,..., 1}
i i
v v q i m m i n
Ο† Ο† +
βˆ’ = βˆ’ + + = βˆ’
= { 2q – m - 2, 2q – 3m - 4, …, 2(q – n(m+1) + 1)+3m}
l
i
The range of | ( ) ( ) | {2 2( 1)( 1) 2 1: ( );1 ;1 }
i
v v q m i l i odd i n l m
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ βˆ’ + ≀ ≀ ≀ ≀
= { 2q – 2l + 1, 2( q – (m+1) - l )+1, …, 2(q – mn - n) + 3}
l
i
The range of | ( ) ( ) | {2 ( 1)(2 3) 2 :( );1 ;1 }
i
v v q m i m l i even i n l m
Ο† Ο†
βˆ’ = βˆ’ + βˆ’ βˆ’ βˆ’ ≀ ≀ ≀ ≀
= { 2( q – m– l )-1, 2( q – 3m –l )-5, …, 2q – (m+1)(2n-3)-3m}
Hence {| ( ) ( ) |: } {1,3,5,...,2 1}
u v uv E q
Ο† Ο†
βˆ’ ∈ = βˆ’ so that the graph G = 1
n
P mK
e is odd graceful.
β– 
3 Concluding Remarks
Graceful and odd gracefulness of a graph are two entirely different concepts. A graph may posses
one or both of these or neither. In the present work we investigate four new families of odd
graceful graphs. To investigate similar results for other graph families and in the context of
different labeling techniques is an open area of research.
Open Problems
1-Let G be the linear 8
kC snake
βˆ’ with m-pendant edges . Is G odd graceful ?
2-Let G be the linear n
kC snake
βˆ’ with m-pendant edges ( n even) . Is G odd graceful ?
International journal on applications of graph theory in wireless ad hoc networks and sensor networks
(GRAPH-HOC) Vol.4, No.4, December 2012
9
References
[1] R. B. Gnanajothi, Topics in Graph Theory, Ph.D. Thesis, Madurai Kamaraj University, (1991).
[2] E.M.Badr, M. I. Moussa and K. Kathiresan, Crown graphs and subdivision of ladders are odd
graceful, International Journal of Computer Mathematics, vol.88,Issue 17, PP. 3570- 3576 (2011)
[3] G. Chartrand and L. Lesniak, Graphs and Digraphs, Chapman and hall/CRC, Boca Raton, London,
New York, Washinton, D. C., 1996.
[4] C. Barrientos, Difference Vertex Labelings, Ph. D. Thesis, University Politecnica De Catalunya,
Spain, 2004.
[5] A. Rosa, Cyclic Steiner Triple Systems and Labelings of Triangular Cacti, Scientia, 5, (1967), 87-95.
[6] E. M. Badr and M. I. Moussa, Odd Graceful Labelings of Syclic Snakes, 1st International Conference
on Mathematics and Statistics, Sharjah, E. U. A, (2010).
Author
El-Sayed Badr received the B.Sc. (Mathematics) the M.Sc. (Pure Mathematics)
degree from Benha University, Benha, Egypt in 1994, 2000 respectively. Also, he
received Ph.D. ( Computer Science) degree from Department of Applied
Informatics, Macedonia University, Thessaloniki, Greece, in 2006. He is a
University lecturer of Computer Science with the Benha University, Faculty of
Science, Department of Mathematics. His current research is Parallel Programming,
linear programming and Graph Theory.

More Related Content

Similar to On the Odd Gracefulness of Cyclic Snakes With Pendant Edges

FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSFURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSFransiskeran
Β 
FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSFURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSgraphhoc
Β 
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles  An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles graphhoc
Β 
machinelearning project
machinelearning projectmachinelearning project
machinelearning projectLianli Liu
Β 
New Classes of Odd Graceful Graphs
New Classes of Odd Graceful GraphsNew Classes of Odd Graceful Graphs
New Classes of Odd Graceful Graphsgraphhoc
Β 
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdf
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdfSome_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdf
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdfmehsinatteya88
Β 
Fine Grained Complexity of Rainbow Coloring and its Variants
Fine Grained Complexity of Rainbow Coloring and its VariantsFine Grained Complexity of Rainbow Coloring and its Variants
Fine Grained Complexity of Rainbow Coloring and its VariantsAkankshaAgrawal55
Β 
New Families of Odd Harmonious Graphs
New Families of Odd Harmonious GraphsNew Families of Odd Harmonious Graphs
New Families of Odd Harmonious GraphsIJMIT JOURNAL
Β 
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsAlgorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsIJERA Editor
Β 
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsAlgorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsIJERA Editor
Β 
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHT
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHTON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHT
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHTijitjournal
Β 
Graph Theory,Graph Terminologies,Planar Graph & Graph Colouring
Graph Theory,Graph Terminologies,Planar Graph & Graph ColouringGraph Theory,Graph Terminologies,Planar Graph & Graph Colouring
Graph Theory,Graph Terminologies,Planar Graph & Graph ColouringSaurabh Kaushik
Β 
Further pure mathmatics 3 vectors
Further pure mathmatics 3 vectorsFurther pure mathmatics 3 vectors
Further pure mathmatics 3 vectorsDennis Almeida
Β 
Fourier-transform analysis of a unilateral fin line and its derivatives
Fourier-transform analysis of a unilateral fin line and its derivativesFourier-transform analysis of a unilateral fin line and its derivatives
Fourier-transform analysis of a unilateral fin line and its derivativesYong Heui Cho
Β 
In insight into QAC2(1) : Dynkin diagrams and properties of roots
In insight into QAC2(1) : Dynkin diagrams and properties of rootsIn insight into QAC2(1) : Dynkin diagrams and properties of roots
In insight into QAC2(1) : Dynkin diagrams and properties of rootsIRJET Journal
Β 
Embedding and np-Complete Problems for 3-Equitable Graphs
Embedding and np-Complete Problems for 3-Equitable GraphsEmbedding and np-Complete Problems for 3-Equitable Graphs
Embedding and np-Complete Problems for 3-Equitable GraphsWaqas Tariq
Β 

Similar to On the Odd Gracefulness of Cyclic Snakes With Pendant Edges (20)

FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSFURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
Β 
FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHSFURTHER RESULTS ON ODD HARMONIOUS GRAPHS
FURTHER RESULTS ON ODD HARMONIOUS GRAPHS
Β 
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles  An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles
An Algorithm for Odd Graceful Labeling of the Union of Paths and Cycles
Β 
machinelearning project
machinelearning projectmachinelearning project
machinelearning project
Β 
New Classes of Odd Graceful Graphs
New Classes of Odd Graceful GraphsNew Classes of Odd Graceful Graphs
New Classes of Odd Graceful Graphs
Β 
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdf
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdfSome_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdf
Some_Properties_for_the_Commutators_of_Special_Linear_Quantum_Groups (12).pdf
Β 
50120130406004 2-3
50120130406004 2-350120130406004 2-3
50120130406004 2-3
Β 
Fine Grained Complexity of Rainbow Coloring and its Variants
Fine Grained Complexity of Rainbow Coloring and its VariantsFine Grained Complexity of Rainbow Coloring and its Variants
Fine Grained Complexity of Rainbow Coloring and its Variants
Β 
New Families of Odd Harmonious Graphs
New Families of Odd Harmonious GraphsNew Families of Odd Harmonious Graphs
New Families of Odd Harmonious Graphs
Β 
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsAlgorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Β 
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in GraphsAlgorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Algorithmic Aspects of Vertex Geo-dominating Sets and Geonumber in Graphs
Β 
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHT
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHTON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHT
ON THE COVERING RADIUS OF CODES OVER Z4 WITH CHINESE EUCLIDEAN WEIGHT
Β 
graph theory
graph theorygraph theory
graph theory
Β 
Optimisation random graph presentation
Optimisation random graph presentationOptimisation random graph presentation
Optimisation random graph presentation
Β 
Graph Theory,Graph Terminologies,Planar Graph & Graph Colouring
Graph Theory,Graph Terminologies,Planar Graph & Graph ColouringGraph Theory,Graph Terminologies,Planar Graph & Graph Colouring
Graph Theory,Graph Terminologies,Planar Graph & Graph Colouring
Β 
Further pure mathmatics 3 vectors
Further pure mathmatics 3 vectorsFurther pure mathmatics 3 vectors
Further pure mathmatics 3 vectors
Β 
PhotonModel
PhotonModelPhotonModel
PhotonModel
Β 
Fourier-transform analysis of a unilateral fin line and its derivatives
Fourier-transform analysis of a unilateral fin line and its derivativesFourier-transform analysis of a unilateral fin line and its derivatives
Fourier-transform analysis of a unilateral fin line and its derivatives
Β 
In insight into QAC2(1) : Dynkin diagrams and properties of roots
In insight into QAC2(1) : Dynkin diagrams and properties of rootsIn insight into QAC2(1) : Dynkin diagrams and properties of roots
In insight into QAC2(1) : Dynkin diagrams and properties of roots
Β 
Embedding and np-Complete Problems for 3-Equitable Graphs
Embedding and np-Complete Problems for 3-Equitable GraphsEmbedding and np-Complete Problems for 3-Equitable Graphs
Embedding and np-Complete Problems for 3-Equitable Graphs
Β 

More from GiselleginaGloria

10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...GiselleginaGloria
Β 
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...GiselleginaGloria
Β 
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...GiselleginaGloria
Β 
2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...GiselleginaGloria
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...GiselleginaGloria
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...GiselleginaGloria
Β 
A Survey on Area Planning for Heterogeneous Networks
A Survey on Area Planning for Heterogeneous NetworksA Survey on Area Planning for Heterogeneous Networks
A Survey on Area Planning for Heterogeneous NetworksGiselleginaGloria
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...GiselleginaGloria
Β 
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...GiselleginaGloria
Β 
2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...GiselleginaGloria
Β 
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)2nd International Conference on Education in Post Pandemic (EDUPAN 2024)
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)GiselleginaGloria
Β 
16th International Conference on Networks & Communications (NeCoM 2024)
16th International Conference on Networks & Communications (NeCoM 2024)16th International Conference on Networks & Communications (NeCoM 2024)
16th International Conference on Networks & Communications (NeCoM 2024)GiselleginaGloria
Β 
11th International Conference on Cybernetics & Informatics (CYBI 2024)
11th International Conference on Cybernetics & Informatics (CYBI 2024)11th International Conference on Cybernetics & Informatics (CYBI 2024)
11th International Conference on Cybernetics & Informatics (CYBI 2024)GiselleginaGloria
Β 
10th International Conference on Natural Language Processing (NATP 2024)
10th International Conference on Natural Language Processing (NATP 2024)10th International Conference on Natural Language Processing (NATP 2024)
10th International Conference on Natural Language Processing (NATP 2024)GiselleginaGloria
Β 
2nd International Conference on Computer Science and Machine Learning (CSML 2...
2nd International Conference on Computer Science and Machine Learning (CSML 2...2nd International Conference on Computer Science and Machine Learning (CSML 2...
2nd International Conference on Computer Science and Machine Learning (CSML 2...GiselleginaGloria
Β 
3rd International Conference on Computing and Information Technology Trends (...
3rd International Conference on Computing and Information Technology Trends (...3rd International Conference on Computing and Information Technology Trends (...
3rd International Conference on Computing and Information Technology Trends (...GiselleginaGloria
Β 
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor Networks
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor NetworksThe Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor Networks
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor NetworksGiselleginaGloria
Β 
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...GiselleginaGloria
Β 
5th International Conference on Networks, Communications, Wireless and Mobile...
5th International Conference on Networks, Communications, Wireless and Mobile...5th International Conference on Networks, Communications, Wireless and Mobile...
5th International Conference on Networks, Communications, Wireless and Mobile...GiselleginaGloria
Β 

More from GiselleginaGloria (19)

10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...
Β 
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...
Embedding of Poly Honeycomb Networks and the Metric dimension of Star of Davi...
Β 
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...
12th International Conference of Artificial Intelligence and Fuzzy Logic (AI ...
Β 
2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...
Β 
A Survey on Area Planning for Heterogeneous Networks
A Survey on Area Planning for Heterogeneous NetworksA Survey on Area Planning for Heterogeneous Networks
A Survey on Area Planning for Heterogeneous Networks
Β 
10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...10th International Conference on Artificial Intelligence and Applications (AI...
10th International Conference on Artificial Intelligence and Applications (AI...
Β 
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...
A Professional QoS Provisioning in the Intra Cluster Packet Level Resource Al...
Β 
2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...2nd International Conference on Computer Science, Engineering and Artificial ...
2nd International Conference on Computer Science, Engineering and Artificial ...
Β 
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)2nd International Conference on Education in Post Pandemic (EDUPAN 2024)
2nd International Conference on Education in Post Pandemic (EDUPAN 2024)
Β 
16th International Conference on Networks & Communications (NeCoM 2024)
16th International Conference on Networks & Communications (NeCoM 2024)16th International Conference on Networks & Communications (NeCoM 2024)
16th International Conference on Networks & Communications (NeCoM 2024)
Β 
11th International Conference on Cybernetics & Informatics (CYBI 2024)
11th International Conference on Cybernetics & Informatics (CYBI 2024)11th International Conference on Cybernetics & Informatics (CYBI 2024)
11th International Conference on Cybernetics & Informatics (CYBI 2024)
Β 
10th International Conference on Natural Language Processing (NATP 2024)
10th International Conference on Natural Language Processing (NATP 2024)10th International Conference on Natural Language Processing (NATP 2024)
10th International Conference on Natural Language Processing (NATP 2024)
Β 
2nd International Conference on Computer Science and Machine Learning (CSML 2...
2nd International Conference on Computer Science and Machine Learning (CSML 2...2nd International Conference on Computer Science and Machine Learning (CSML 2...
2nd International Conference on Computer Science and Machine Learning (CSML 2...
Β 
3rd International Conference on Computing and Information Technology Trends (...
3rd International Conference on Computing and Information Technology Trends (...3rd International Conference on Computing and Information Technology Trends (...
3rd International Conference on Computing and Information Technology Trends (...
Β 
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor Networks
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor NetworksThe Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor Networks
The Neighborhood Broadcast Problem in Wireless Ad Hoc Sensor Networks
Β 
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...
A PROPOSAL ANALYTICAL MODEL AND SIMULATION OF THE ATTACKS IN ROUTING PROTOCOL...
Β 
5th International Conference on Networks, Communications, Wireless and Mobile...
5th International Conference on Networks, Communications, Wireless and Mobile...5th International Conference on Networks, Communications, Wireless and Mobile...
5th International Conference on Networks, Communications, Wireless and Mobile...
Β 

Recently uploaded

Current Transformer Drawing and GTP for MSETCL
Current Transformer Drawing and GTP for MSETCLCurrent Transformer Drawing and GTP for MSETCL
Current Transformer Drawing and GTP for MSETCLDeelipZope
Β 
Application of Residue Theorem to evaluate real integrations.pptx
Application of Residue Theorem to evaluate real integrations.pptxApplication of Residue Theorem to evaluate real integrations.pptx
Application of Residue Theorem to evaluate real integrations.pptx959SahilShah
Β 
Sachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Sachpazis Costas: Geotechnical Engineering: A student's Perspective IntroductionSachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Sachpazis Costas: Geotechnical Engineering: A student's Perspective IntroductionDr.Costas Sachpazis
Β 
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...9953056974 Low Rate Call Girls In Saket, Delhi NCR
Β 
What are the advantages and disadvantages of membrane structures.pptx
What are the advantages and disadvantages of membrane structures.pptxWhat are the advantages and disadvantages of membrane structures.pptx
What are the advantages and disadvantages of membrane structures.pptxwendy cai
Β 
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130Suhani Kapoor
Β 
HARMONY IN THE NATURE AND EXISTENCE - Unit-IV
HARMONY IN THE NATURE AND EXISTENCE - Unit-IVHARMONY IN THE NATURE AND EXISTENCE - Unit-IV
HARMONY IN THE NATURE AND EXISTENCE - Unit-IVRajaP95
Β 
SPICE PARK APR2024 ( 6,793 SPICE Models )
SPICE PARK APR2024 ( 6,793 SPICE Models )SPICE PARK APR2024 ( 6,793 SPICE Models )
SPICE PARK APR2024 ( 6,793 SPICE Models )Tsuyoshi Horigome
Β 
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escortsranjana rawat
Β 
Heart Disease Prediction using machine learning.pptx
Heart Disease Prediction using machine learning.pptxHeart Disease Prediction using machine learning.pptx
Heart Disease Prediction using machine learning.pptxPoojaBan
Β 
power system scada applications and uses
power system scada applications and usespower system scada applications and uses
power system scada applications and usesDevarapalliHaritha
Β 
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur Escorts
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur EscortsHigh Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur Escorts
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur EscortsCall Girls in Nagpur High Profile
Β 
Microscopic Analysis of Ceramic Materials.pptx
Microscopic Analysis of Ceramic Materials.pptxMicroscopic Analysis of Ceramic Materials.pptx
Microscopic Analysis of Ceramic Materials.pptxpurnimasatapathy1234
Β 
Introduction to Microprocesso programming and interfacing.pptx
Introduction to Microprocesso programming and interfacing.pptxIntroduction to Microprocesso programming and interfacing.pptx
Introduction to Microprocesso programming and interfacing.pptxvipinkmenon1
Β 
College Call Girls Nashik Nehal 7001305949 Independent Escort Service Nashik
College Call Girls Nashik Nehal 7001305949 Independent Escort Service NashikCollege Call Girls Nashik Nehal 7001305949 Independent Escort Service Nashik
College Call Girls Nashik Nehal 7001305949 Independent Escort Service NashikCall Girls in Nagpur High Profile
Β 
Biology for Computer Engineers Course Handout.pptx
Biology for Computer Engineers Course Handout.pptxBiology for Computer Engineers Course Handout.pptx
Biology for Computer Engineers Course Handout.pptxDeepakSakkari2
Β 
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...VICTOR MAESTRE RAMIREZ
Β 

Recently uploaded (20)

Current Transformer Drawing and GTP for MSETCL
Current Transformer Drawing and GTP for MSETCLCurrent Transformer Drawing and GTP for MSETCL
Current Transformer Drawing and GTP for MSETCL
Β 
Application of Residue Theorem to evaluate real integrations.pptx
Application of Residue Theorem to evaluate real integrations.pptxApplication of Residue Theorem to evaluate real integrations.pptx
Application of Residue Theorem to evaluate real integrations.pptx
Β 
Sachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Sachpazis Costas: Geotechnical Engineering: A student's Perspective IntroductionSachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Sachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Β 
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...
πŸ”9953056974πŸ”!!-YOUNG call girls in Rajendra Nagar Escort rvice Shot 2000 nigh...
Β 
What are the advantages and disadvantages of membrane structures.pptx
What are the advantages and disadvantages of membrane structures.pptxWhat are the advantages and disadvantages of membrane structures.pptx
What are the advantages and disadvantages of membrane structures.pptx
Β 
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130
VIP Call Girls Service Kondapur Hyderabad Call +91-8250192130
Β 
HARMONY IN THE NATURE AND EXISTENCE - Unit-IV
HARMONY IN THE NATURE AND EXISTENCE - Unit-IVHARMONY IN THE NATURE AND EXISTENCE - Unit-IV
HARMONY IN THE NATURE AND EXISTENCE - Unit-IV
Β 
SPICE PARK APR2024 ( 6,793 SPICE Models )
SPICE PARK APR2024 ( 6,793 SPICE Models )SPICE PARK APR2024 ( 6,793 SPICE Models )
SPICE PARK APR2024 ( 6,793 SPICE Models )
Β 
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts
(MEERA) Dapodi Call Girls Just Call 7001035870 [ Cash on Delivery ] Pune Escorts
Β 
Heart Disease Prediction using machine learning.pptx
Heart Disease Prediction using machine learning.pptxHeart Disease Prediction using machine learning.pptx
Heart Disease Prediction using machine learning.pptx
Β 
power system scada applications and uses
power system scada applications and usespower system scada applications and uses
power system scada applications and uses
Β 
Exploring_Network_Security_with_JA3_by_Rakesh Seal.pptx
Exploring_Network_Security_with_JA3_by_Rakesh Seal.pptxExploring_Network_Security_with_JA3_by_Rakesh Seal.pptx
Exploring_Network_Security_with_JA3_by_Rakesh Seal.pptx
Β 
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur Escorts
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur EscortsHigh Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur Escorts
High Profile Call Girls Nagpur Meera Call 7001035870 Meet With Nagpur Escorts
Β 
Microscopic Analysis of Ceramic Materials.pptx
Microscopic Analysis of Ceramic Materials.pptxMicroscopic Analysis of Ceramic Materials.pptx
Microscopic Analysis of Ceramic Materials.pptx
Β 
Introduction to Microprocesso programming and interfacing.pptx
Introduction to Microprocesso programming and interfacing.pptxIntroduction to Microprocesso programming and interfacing.pptx
Introduction to Microprocesso programming and interfacing.pptx
Β 
College Call Girls Nashik Nehal 7001305949 Independent Escort Service Nashik
College Call Girls Nashik Nehal 7001305949 Independent Escort Service NashikCollege Call Girls Nashik Nehal 7001305949 Independent Escort Service Nashik
College Call Girls Nashik Nehal 7001305949 Independent Escort Service Nashik
Β 
β˜… CALL US 9953330565 ( HOT Young Call Girls In Badarpur delhi NCR
β˜… CALL US 9953330565 ( HOT Young Call Girls In Badarpur delhi NCRβ˜… CALL US 9953330565 ( HOT Young Call Girls In Badarpur delhi NCR
β˜… CALL US 9953330565 ( HOT Young Call Girls In Badarpur delhi NCR
Β 
Biology for Computer Engineers Course Handout.pptx
Biology for Computer Engineers Course Handout.pptxBiology for Computer Engineers Course Handout.pptx
Biology for Computer Engineers Course Handout.pptx
Β 
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...
VICTOR MAESTRE RAMIREZ - Planetary Defender on NASA's Double Asteroid Redirec...
Β 
Call Us -/9953056974- Call Girls In Vikaspuri-/- Delhi NCR
Call Us -/9953056974- Call Girls In Vikaspuri-/- Delhi NCRCall Us -/9953056974- Call Girls In Vikaspuri-/- Delhi NCR
Call Us -/9953056974- Call Girls In Vikaspuri-/- Delhi NCR
Β 

On the Odd Gracefulness of Cyclic Snakes With Pendant Edges

  • 1. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 DOI : 10.5121/jgraphoc.2012.4401 1 On the Odd Gracefulness of Cyclic Snakes With Pendant Edges E. M. Badr Department of Scientific Computing, Faculty of Computer Science and Informatics, Benha University, Benha, Egypt badrgraph@gmail.com ABSTRACT Graceful and odd gracefulness of a graph are two entirely different concepts. A graph may posses one or both of these or neither. We present four new families of odd graceful graphs. In particular we show an odd graceful labeling of the linear 4 1 kC snake mK βˆ’ e and therefore we introduce the odd graceful labeling of 4 1 kC snake mK βˆ’ e ( for the general case ). We prove that the subdivision of linear 3 kC snake βˆ’ is odd graceful. We also prove that the subdivision of linear 3 kC snake βˆ’ with m-pendant edges is odd graceful. Finally, we present an odd graceful labeling of the crown graph 1 n P mK e . KEYWORDS Graph theory, odd graceful labeling, path, cyclic snakes, pendant edges. 1. INTRODUCTION The graphs considered here will be finite, undirected and simple. The symbols V(G) and E(G) will denote the vertex set and edge set of a graph G respectively. p and q denote the number of vertices and edges of G respectively. A graph G of size q is odd-graceful, if there is an injection Ο† from V(G) to {0, 1, 2, …, 2q-1} such that, when each edge xy is assigned the label or weight |Ο† (x) - Ο† (y)|, the resulting edge labels are {1, 3, 5, …, 2q-1}. This definition was introduced in 1991 by Gnanajothi [1] who proved that the class of odd graceful graphs lies between the class of graphs with Ξ±-labelings and the class of bipartite graphs. We denote the crown graphs ( the graphs obtained by joining a single pendant edge to each vertex of Cn ) by 1 n C K , therefore the crown graphs (the graphs obtained by joining m-pendant edges to each vertex of Cn ) by 1 n C mK . Gnanajothi [1] proved that 1 n C K is odd graceful if n is even. Badr et al [2] proved that 1 n C mK is odd graceful if n is even. A n kC snake βˆ’ is a connected graph with k blocks, each of the blocks is isomorphic to the cycle Cn, such that the block-cut-vertex graph is a path. Following [3], by a block-cut-vertex graph of a graph G we mean the graph whose vertices are the blocks and cut-vertices of G where two vertices are adjacent if and only if one vertex is a block and the other is a cut-vertex belonging to The block. We also call a n kC snake βˆ’ as a cyclic snake. This graph was first introduced by
  • 2. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 2 Barrientos [4], as generalization of the concept of triangular snake introduced by Rosa [5]. Let G be a n kC snake βˆ’ with k β‰₯ 2. Let u1, u2, . . ., uk-1 be the consecutive cut-vertices of G. Let di be the distance between vi and vi+1 in G, 1 2 i k ≀ ≀ βˆ’ . The string (d1, d2, … , dk-2 ) of integers, characterizes the graph G in the class of n-cyclic snakes. The n kC snake βˆ’ contains q= nk edges and p = ( n - 1 )k + 1 vertices. Among these vertices, k – 1 vertices have degree 4 and the other vertices of degree 2. Now, let us consider a 4 kC snake βˆ’ . The first non trivial quadrilateral snake is 4 2C snake βˆ’ as shown in Figure 1. Two different 4 kC snake βˆ’ can be constructed from a 4 ( 1) k C snake βˆ’ βˆ’ . Figure 1. 2C4-snake with a cut-vertex Example 1.1 We can construct two different 4 3C snake βˆ’ from a 4 2C snake βˆ’ , the first is with string ( 1 ) ( Figure 2a ) and the second is with string ( 2 ) ( Figure 2b ) . a) b) Figure 2. 3C4-snakes with string 1 and string 2 respectively. Badr and Mousa [6] proved that kC4- snake, linear kCn- snake , even kC8 - snake and even kC12- snakes are odd graceful. We denote the crown snakes ( the graphs obtained by joining m-pendant edges to each vertex of kCn-snake ) by 1 n kC snake mK βˆ’ e . Definition 1.2 The kCn-snake is called linear, if the block-cut-vertex graph of kCn-snake has the property that the distance between any two consecutive cut-vertices is 2 n ο£― ο£Ί ο£― ο£Ί ο£° ο£» . In this work we present four new families of odd graceful graphs. In particular we show that an odd graceful labeling of the linear 4 1 kC snake mK βˆ’ e and therefore we introduce the odd graceful labeling of 4 1 kC snake mK βˆ’ e ( for the general case ). We prove that the subdivision of linear 3 kC snake βˆ’ is odd graceful. We also prove that the subdivision of linear 3 kC snake βˆ’ with
  • 3. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 3 m-pendant edges is odd graceful. Finally, we present an odd graceful labeling of the crown graph 1 n P mK e . 2 The Results Theorem 2.1 The linear 4 1 kC snake mK βˆ’ e is odd graceful. Proof. Let G = linear 4 1 kC snake mK βˆ’ e with the vertices wi , uj and vj where i = 0,1, 2, …, k, j = 0,1, 2, …, k-1. In order to get the linear 4 1 kC snake mK βˆ’ e , we add m-pendant edges wi l , uj l and vj l to each vertex of wi , uj and vj respectively such that l=1,2, …, m. Now, the graph 4 1 kC snake mK βˆ’ e has the vertices wi , uj , vj , wi l , uj l and vj l such that i = 0,1, 2, …, k, j = 0,1, 2, …, k-1 and l = 1, 2, …, m. Figure 3. 4 1 3 2 C snake K βˆ’ e is odd graceful Clearly the linear 4 1 kC snake mK βˆ’ e has p = (3k+1)(m+1) vertices and q = 4k+m(3k+1) edges. Let us consider the following numbering Ο† of the vertices of the graph G : Ο† (wi) = 2i(m + 1) i = 0, 1, 2, …, k. Ο† (ui) = 2q – 2i(m + 1 ) - 1 i = 0, 1, 2, …, k. Ο† (vi) = 2q – 4k(m + 1 ) – 2i - 1 i = 0, 1, 2, …, k. Ο† ( wl 0 ) = 2l – 1, l = 1, 2, …, m. Ο† (wi l ) = 2(q-l + m - i(m+1) +1 i = 1, 2, …, k. Ο† (ui l ) = 2 ( l+ i( m + 1) ) i = 0, 1, 2, …, k-1 , l = 1, 2, …, m. Ο† (vi l ) = 4( q – 2k( m + 1) ) – 2( l + 1 + i( m + 3) ) i = 0, 1, 2, …, k-1 , l = 1, 2, …, m.
  • 4. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 4 (a) {0 0 1 1 0 0 1 0 1 1 1 0 1 1 ( ) max 2 ( 1), 2 - 2 ( 1 ) - 1, 2 - 1, max max max 2 - 4 ( 1 ) - 2 - 1, 2( - - ( 1) 1, 2 ( ( 1) ), max max max 4( max v V i k i k l m i k i k i k l m l m i k l m Max v i m q i m l q k m i q l m i m l i m Ο† ∈ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀ βˆ’ ≀ ≀ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀ = + + + + + + + + - 2 ( 1) ) - 2( 1 ( 3) ) q k m l i m ο£Ό + + + + ο£½ ο£Ύ = 2q – 1, the maximum value of all odds. . Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}. (b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}. (c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1, 2q-1]. The range of | ( ) ( ) | {2 4 ( 1) 2 ( 2) 1: 0,1,2,..., 1} i i v w q k m i m i k Ο† Ο† βˆ’ = βˆ’ + βˆ’ + βˆ’ = βˆ’ = { 2q - 4k(m+1) - 1, …, 2q -4k(m+1) – 2m - 5, … , 2q -6km -8k +2(m+2) - 1 } i+1 The range of | ( ) ( ) | {2 4 ( 1) 2 ( 2) 2 3: 0,1,2,3,..., 1} i v w q k m i m m i k Ο† Ο† βˆ’ = βˆ’ + βˆ’ + βˆ’ βˆ’ = βˆ’ = { 2q – 4k(m+1)-8k+1, 2q-4k(m+1)-4m-7, …, 2q-6km-8k+1} i T he range of | ( ) ( ) | {2 4 ( 1) 1 : 0,1, 2, 3,..., 1} i u w q i m i k Ο† Ο† βˆ’ = βˆ’ + βˆ’ = βˆ’ = { 2q-1, 2q-4(m+1) - 1, …, 2q-4(k-1)(m+1) - 1} i The range of | ( ) ( ) | {2 4 ( 1) 2 3: 0,1,2,3,..., 1} i u w q i m m i k Ο† Ο† βˆ’ = βˆ’ + βˆ’ βˆ’ = βˆ’ = { 2q-2m-3, 2q-6m-7 …, 2q-4(k-1)(m+1) – 2m-3} l 0 0 The range of | ( ) ( ) | {2 1: 1,2,3,..., } w w l l m Ο† Ο† βˆ’ = βˆ’ = = { 1, 3, …, 2m -1} l i The range of | ( ) ( ) | {2( 2 ( 1)) 1: 1,2,3,..., , 1,2,3,..., } i w w q l m i m i k l m Ο† Ο† βˆ’ = βˆ’ + βˆ’ + + = = = { 2( q –l – m) – 3, 2( q – l – 3m) – 7, …, 2(q-l+m-2k(m+1))+1} l i The range of | ( ) ( ) | {2( 2 ( 1) 1: 0,1,2,3,..., 1; 1,2,3,..., } i u u q l i m i k l m Ο† Ο† βˆ’ = βˆ’ βˆ’ + βˆ’ = βˆ’ = = { 2(q-l)-1, 2(q-l-2(m+1)-1, …, 2(q-l-2(k-1)(m+1)-1} l i The range of | ( ) ( )| {2( 2 ( 1) ( 2)) 1:0 1;1 } i v v q k m l i m i k l m Ο† Ο† βˆ’ = βˆ’ + βˆ’ βˆ’ + βˆ’ ≀ ≀ βˆ’ ≀ ≀ = { 2(q-2k(m+1)-l)-1, 2(q-2k(m+1)-l-(m+2))-1, …, 2[q-2k(m+1)-l-(k-1)(m+2)]-1} Hence {| ( ) ( ) |: } {1,3,5,...,2 1} u v uv E q Ο† Ο† βˆ’ ∈ = βˆ’ so that the graph G is odd graceful.β–  Theorem 2.2 The 4 1 kC snake mK βˆ’ e is odd graceful. Proof. Let G = 4 1 kC snake mK βˆ’ e . The graph G obtained by joining m-pendant edges to each vertex of 4 kC snake βˆ’ . Now, we are running the following steps sequentially in order to prove the Theorem.
  • 5. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 5 Figure 4 . 4 1 4 2 C K snake βˆ’ e is odd graceful Step 1 . Since 4 kC snake βˆ’ is a bipartite graph so it has one partite set has black vertices and the other has white vertices as shown in Figure 4. Put black vertices in a string, ordered by diagonals from left to right and inside each diagonal from bottom to top, assign to them from an arithmetic progression of difference 2, which first term is zero, counting until the last black vertex has been numbered. Similarly, put the white vertices on a string, ordered for diagonals from left to right and inside each diagonal from top to bottom. Starting with the first diagonal assign numbers from an arithmetic progression of difference 4, which first term is 2q-1 where q is the size of G, while to move to another diagonal we use an arithmetic progression of difference 2 but the arithmetic progression of difference 4 is used inside each diagonal, continuing until the last white vertex has been numbered. Step 2 . In this step, we are labeling the vertices of m-pendant edges which contact with black diagonals, from left to right and inside each black diagonal from bottom to top, assign to them from an arithmetic progression of difference 2, which first term is one, when to move to a new vertex of the block diagonal, the first vertex of m-pendant edges is labeled by an arithmetic progression of difference 4, but the arithmetic progression of difference 2 has been used with the remain ( m-1 ) vertices of m-pendant edges. We move from a vertex to another of the black diagonals until the last black vertex. Step 3 . Finally, we are labeling the vertices of m-pendant edges which contact with the white diagonals, from right to left an inside each white diagonal from bottom to top, assign to them from an arithmetic progression of difference 2, which first term is z such that z = y + 2 where y is the last vertex labeling of the black diagonals, when to move to a new vertex of the white diagonal, the first vertex of m-pendant edges is labeled by an arithmetic progression of difference 6, but the arithmetic progression of difference 2 has been used with the remain ( m-1 ) vertices of m- pendant edges. When to move to another diagonal we use an arithmetic progression of difference 4 but the arithmetic progression of difference 2 has been used with the remain ( m-1 ) vertices of m-pendant edges. We move from a vertex to another of the white diagonals until the last white vertex. We have the complete proof of the Theorem by running the above steps. β–  Theorem 2.3 The subdivision of linear 3 kC snake βˆ’ is odd graceful. Proof : We prove that the subdivision of graph S ( kC3-snake ) ( obtained by subdividing every edge of kC3-snake exactly once ) is odd graceful. 0 2 4 6 8 1 0 1 3 7 9 1 3 1 5 1 9 2 1 2 5 2 7 3 1 3 3 8 3 7 9 7 7 7 3 6 9 6 7 6 3 1 2 1 4 2 0 2 2 2 6 2 8 3 4 3 6 4 2 4 4 4 8 5 0 5 6 5 8
  • 6. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 6 Let u0, u1, . . . , uk, v0, v1, . . . , vk-1 be the vertices of the kC3-snake . Let yi be the newly added vertex between ui and ui+1 where i = 0, 1, . . . , k-1 but wi be the newly added vertex between uj,vj and vj ,uj+1 ( from left to right ) such that i = 0,1, . . . ,2k-1 and j= 0,1, . . . , k-1 (Figure 5). Figure 5. S ( 3C3-snake ) is odd graceful Clearly S ( kC3-snake ) has p = ( n + 2 )k + 1 vertices and q = 2nk edges. Let us consider the following numbering Ο† of the vertices of S ( kC3-snake ): Ο† ( ui ) = 4i , where i = 0, 1, 2, . . . , k. Ο† ( vi ) = 4i + 2 , where i = 0, 1, 2, . . . , k – 1. Ο† ( wi ) = 2q -2i -1 , where i = 0, 1, 2, . . . , 2k – 1. Ο† ( yi ) = 2q - 8k – 4i - 1 , where i = 0, 1, 2, . . . , k – 1. (a) {0 0 1 0 2 1 0 1 ( ) max 4 , 4 2, 2 - 2 -1, 2 -8 - 4 -1 v V Max v i i q i q k i max max max max ΞΉ ΞΊ ΞΉ ΞΊ ΞΉ ΞΊ ΞΉ ΞΊ Ο† ∈ ≀ ≀ ≀ ≀ βˆ’ ≀ ≀ βˆ’ ≀ ≀ βˆ’ ο£Ό = + ο£½ ο£Ύ = 2q – 1, the maximum value of all odds. . Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}. (b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}. (c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1, 2q-1]. Let r be the number of block which has the vertex vi or ui where i = 1, 2, . . . , k. The range of | ( ) ( ) | {2 8 8 1: 0,1,2,..., 1} i i u y q k i i k Ο† Ο† βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’ = { 2q – 8k -1, …, 2q – 8k- 9, … , 2q -16k + 7 } 1 The range of | ( ) ( ) | {2 8 8 5: 0,1,2,..., 1} i i y u q k i i k Ο† Ο† + βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’ = { 2q – 8k -5, …, 2q – 8k - 13, … , 2q -16k + 3 } 1 The range of | ( ) ( ) | {2 6 2 1: 0,1,2,..., } i i r u w q i r i k Ο† Ο† + βˆ’ βˆ’ = βˆ’ βˆ’ + = = { 2q – 1, …, 2q – 7, … , 2q - 8k + 1 } The range of | ( ) ( ) | {2 6 2 3: 0,1,2,..., 1} i i r v w q i r i k Ο† Ο† + βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’ = { 2q – 5, …, 2q – 13, … , 2q - 8k + 3 } 1 The range of | ( ) ( ) | {2 6 2 1: 0,1,2,..., 1} i i r v w q i r i k Ο† Ο† + βˆ’ βˆ’ = βˆ’ βˆ’ βˆ’ = βˆ’ = { 2q – 3, …, 2q – 11, … , 2q - 8k + 5 }
  • 7. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 7 Hence {| ( ) ( ) |: } {1,3,5,...,2 1} u v uv E q Ο† Ο† βˆ’ ∈ = βˆ’ so that the graph S ( kC3-snake ) is odd graceful. β–  Theorem 2.4 The subdivision of linear 3 kC snake βˆ’ with m-pendant edges is odd graceful. Proof. We prove that the linear 3 1 ( ) S kC snake mK βˆ’ e is odd graceful , where 3 ( ) S kC snake βˆ’ is obtained by subdividing every edge of kC3-snake exactly once and mK1 are m-pendant edges which join to every vertex of the graph 3 ( ) S kC snake βˆ’ . Let u1, u2, . . . , uk+1, w1, w2, . . . , vk be the vertices of the kC3-snake . Let yi be the newly added vertex between ui and ui+1 where i = 1, . . . , k while vi be the newly added vertex between ui,wi where i = 1, . . . , k. Finally zi be the newly added vertex between wi ,ui+1 wher i = 1, 2, . . . ,k. In order to get the graph G = linear 3 1 ( ) S kC snake mK βˆ’ e , we add m-pendant edges l i u , l i y , l i v , l i w and l i z to each vertex of i u , i y , i v , i w and i z respectively. Clearly the graph G has p = (5k+1)m vertices and q = (5m + 6) (k - 1) + m edges. Define : ( ) {0,1,2,...,2 1} V G q Ο• β†’ βˆ’ as follows: ( ) 4( 1)( 1) 1 1 i u m i i k Ο† = + βˆ’ ≀ ≀ + ( ) 2 (2 4) 2 3 1 i v q m i m i k Ο† = βˆ’ + + + ≀ ≀ ( ) 2( 1)(2 1) 1 i w m i i k Ο† = + βˆ’ ≀ ≀ ( ) 4( 1)( ) 4 3 1 i y m k i m i k Ο† = + βˆ’ + + ≀ ≀ ( ) 2 2 ( 2) 1 1 i z q i m i k Ο† = βˆ’ + + ≀ ≀ ( ) 4 ( 1) 2( 1) 1 ; 1 l i v i m l m i k l m Ο† = + + βˆ’ βˆ’ ≀ ≀ ≀ ≀ ( ) 2 2 ( 2) 2( ) 3 1 ; 1 l i w q i m l m i k l m Ο† = βˆ’ + βˆ’ βˆ’ + ≀ ≀ ≀ ≀ ( ) 4 ( 1) 2( 1) 1 ; 1 l i z i m k m i k l m Ο† = + + βˆ’ βˆ’ ≀ ≀ ≀ ≀ 1 ( ) 2 2 (2 4) 2 2 1 l y q l m k m l m Ο† = βˆ’ βˆ’ + βˆ’ βˆ’ ≀ ≀ ( ) 2 ( 1) 2 ( 1) ( ); 2,3,4,..., ( ),1 l i y q i m l m k k odd i n i even l m Ο† = βˆ’ + βˆ’ + + = ≀ ≀ ( ) 2 ( 1) 2 ( 1) 2 ( ); 2,3,4,..., ( ),1 l i y q i m l m k k odd i n i odd l m Ο† = βˆ’ + βˆ’ + + + = ≀ ≀ ( ) 2 ( 1) 2 ( 1) 2 ( ); 2,3,4,..., ( ),1 l i y q i m l m k k even i n i even l m Ο† = βˆ’ + βˆ’ + + + = ≀ ≀ ( ) 2 ( 1) 2 ( 1) ( ); 2,3,4,..., ( ),1 l i y q i m l m k k even i n i odd l m Ο† = βˆ’ + βˆ’ + + = ≀ ≀ 1 ( ) 2 1 1 l u l l m Ο† = + ≀ ≀ ( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1 l i u q i m l m k m k even i n n even l m Ο† = + + βˆ’ βˆ’ + βˆ’ βˆ’ = βˆ’ ≀ ≀ ( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1 l i u q i m l m k m k even i n n odd l m Ο† = + + βˆ’ βˆ’ + βˆ’ + = βˆ’ ≀ ≀ ( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1 l i u q i m l m k m k odd i n n even l m Ο† = + + βˆ’ βˆ’ + βˆ’ + = βˆ’ ≀ ≀ ( ) 2 ( 1) 2 (3 4) 1 ( ); 2,3,4,..., 1( );1 l i u q i m l m k m k odd i n n odd l m Ο† = + + βˆ’ βˆ’ + βˆ’ βˆ’ = βˆ’ ≀ ≀ ( ) 2 2 (2 4) 2 5 1 l n u q l m n m l m Ο† = βˆ’ βˆ’ + + + ≀ ≀ Then clearly the mapping Ο† is an odd graceful labeling.β– 
  • 8. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 8 Theorem 2.5 The crown graph 1 n P mK e is odd graceful. Proof. We can see the crown graph G = 1 n P mK as the path Pn which has the vertices ( v1, v2, v3 …, vn) such that each vertex vi adjacent to m pendent edges vi l where i = 1, 2, 3, . . ., n and l = 1, 2, 3, . . ., m. Let us consider the following numbering Ο† of the vertices of G. Ο† (vi) = (m + 1 )( i – 1 ), ( i odd ), i = 1, 2, …, n. Ο† (vi) = 2q – (m + 1 )( i – 1 ) - m, ( i even ), i = 1, 2, …, n. Ο† (vi k ) = 2q – (m + 1 )( i – 1 ) - 2l + 1, ( i odd ), i = 1, 2, …, n, l = 1, 2, …, m. Ο† (vi k ) = (m+1)(i+1)+2k-(m+1) , ( i even ), i = 1, 2, …, n, l = 1, 2, …, m. (a) { 1 ,i odd i odd i even 1 1 1 1 ,i even 1 Max ( ) max ( + 1 )( - 1 ), 2 - ( + 1 )( - 1 ) - , 2 - ( + 1 )( - 1 ) - 2 + 1, max max max 2 - ( + 1 )( - 2 ) + 2 max l m v V i n i n i n l m i n v m i q m i m q m i l q m i l Ο† ≀ ≀ ∈ ≀ ≀ ≀ ≀ ≀ ≀ ≀ ≀ ≀ ≀ = ο£Ό ο£½ ο£Ύ = 2q – 1, the maximum value of all odds. . Thus Ο† (v) ∈ {0, 1, 2,…,2q – 1}. (b) Clearly Ο† is a one – to – one mapping from the vertex set of G to {0, 1, 2, …, 2q-1}. (c) It remains to show that the labels of the edges of G are all the odd integers of the interval [1, 2q-1]. 1 The range of | ( ) ( ) | {2 2 ( 1) : 1,2,..., 1} i i v v q i m m i n Ο† Ο† + βˆ’ = βˆ’ + + = βˆ’ = { 2q – m - 2, 2q – 3m - 4, …, 2(q – n(m+1) + 1)+3m} l i The range of | ( ) ( ) | {2 2( 1)( 1) 2 1: ( );1 ;1 } i v v q m i l i odd i n l m Ο† Ο† βˆ’ = βˆ’ + βˆ’ βˆ’ + ≀ ≀ ≀ ≀ = { 2q – 2l + 1, 2( q – (m+1) - l )+1, …, 2(q – mn - n) + 3} l i The range of | ( ) ( ) | {2 ( 1)(2 3) 2 :( );1 ;1 } i v v q m i m l i even i n l m Ο† Ο† βˆ’ = βˆ’ + βˆ’ βˆ’ βˆ’ ≀ ≀ ≀ ≀ = { 2( q – m– l )-1, 2( q – 3m –l )-5, …, 2q – (m+1)(2n-3)-3m} Hence {| ( ) ( ) |: } {1,3,5,...,2 1} u v uv E q Ο† Ο† βˆ’ ∈ = βˆ’ so that the graph G = 1 n P mK e is odd graceful. β–  3 Concluding Remarks Graceful and odd gracefulness of a graph are two entirely different concepts. A graph may posses one or both of these or neither. In the present work we investigate four new families of odd graceful graphs. To investigate similar results for other graph families and in the context of different labeling techniques is an open area of research. Open Problems 1-Let G be the linear 8 kC snake βˆ’ with m-pendant edges . Is G odd graceful ? 2-Let G be the linear n kC snake βˆ’ with m-pendant edges ( n even) . Is G odd graceful ?
  • 9. International journal on applications of graph theory in wireless ad hoc networks and sensor networks (GRAPH-HOC) Vol.4, No.4, December 2012 9 References [1] R. B. Gnanajothi, Topics in Graph Theory, Ph.D. Thesis, Madurai Kamaraj University, (1991). [2] E.M.Badr, M. I. Moussa and K. Kathiresan, Crown graphs and subdivision of ladders are odd graceful, International Journal of Computer Mathematics, vol.88,Issue 17, PP. 3570- 3576 (2011) [3] G. Chartrand and L. Lesniak, Graphs and Digraphs, Chapman and hall/CRC, Boca Raton, London, New York, Washinton, D. C., 1996. [4] C. Barrientos, Difference Vertex Labelings, Ph. D. Thesis, University Politecnica De Catalunya, Spain, 2004. [5] A. Rosa, Cyclic Steiner Triple Systems and Labelings of Triangular Cacti, Scientia, 5, (1967), 87-95. [6] E. M. Badr and M. I. Moussa, Odd Graceful Labelings of Syclic Snakes, 1st International Conference on Mathematics and Statistics, Sharjah, E. U. A, (2010). Author El-Sayed Badr received the B.Sc. (Mathematics) the M.Sc. (Pure Mathematics) degree from Benha University, Benha, Egypt in 1994, 2000 respectively. Also, he received Ph.D. ( Computer Science) degree from Department of Applied Informatics, Macedonia University, Thessaloniki, Greece, in 2006. He is a University lecturer of Computer Science with the Benha University, Faculty of Science, Department of Mathematics. His current research is Parallel Programming, linear programming and Graph Theory.