Mathematics and Statistics 10(1): 140-144, 2022
DOI: 10.13189/ms.2022.100111
http://www.hrpub.org
On Recent Advances in Divisor Cordial Labeling of
Graphs
Vishally Sharma, A. Parthiban
*
Department of Mathematics, Lovely Professional University, Punjab, India
Received July 19, 2021; Revised September 23, 2021; Accepted October 17, 2021
Cite This Paper in the following Citation Styles
(a): [1] Vishally Sharma, A. Parthiban, ”On Recent Advances in Divisor Cordial Labeling of Graphs,” Mathematics and Statistics, Vol.10, No.1, pp. 140-144,
2022. DOI: 10.13189/ms.2022.100111
(b): Vishally Sharma, A. Parthiban, (2022). On Recent Advances in Divisor Cordial Labeling of Graphs. Mathematics and Statistics, 10(1), 140-144. DOI:
10.13189/ms.2022.100111
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the Creative Commons Attribution License 4.0 International License
Abstract An assignment of intergers to the vertices of
a graph
¯
G subject to certain constraints is called a vertex
labeling of
¯
G. Different types of graph labeling techniques
are used in the field of coding theory, cryptography, radar,
missile guidance, x-ray crystallography etc. A DCL of
¯
G is a
bijective function
¯
f from node set
¯
V of
¯
G to {1, 2, 3, ..., |
¯
V |}
such that for each edge rs, we allot 1 if
¯
f (r) divides
¯
f (s) or
¯
f (s) divides
¯
f (r) & 0 otherwise, then the absolute difference
between the number of edges having 1 & the number of edges
having 0 do not exceed 1, i.e., |e ¯
f
(0) − e ¯
f
(1)|≤ 1. If
¯
G
permits a DCL, then it is called a DCG. A complete graph
K
n
, is a graph on n nodes in which any 2 nodes are adjacent
and lilly graph I
n
is formed by 2K
1,n
joining 2P
n
,n ≥ 2
sharing a common node. i.e., I
n
=2K
1,n
+2P
n
, where K
1,n
is a complete bipartite graph & P
n
is a path on n nodes. In
this paper, we propose an interesting conjecture concerning
DCL for a given
¯
G, besides, discussing certain general results
concerning DCL of complete graph K
n
−related graphs. We
also prove that I
n
admits a DCL for all n ≥ 2. Further, we
establish the DCL of some I
n
−related graphs in the context
of some graph operations such as duplication of a node by an
edge, node by a node, extension of a node by a node, switching
of a node, degree splitting graph, & barycentric subdivision of
the given
¯
G.
Keywords Graph Labeling, DCL, Lilly Graph
1 Introduction
By
¯
G, we denote a simple, finite, & undirected graph with
node set
¯
V & edge set
¯
E. An allocation of labels to nodes
or edges or sometimes both, under some constraints is called
as graph labeling. Graph labeling is a close association of
graph theory & number theory. Being interdisciplinary, graph
labeling is attracting the attention of numerous researchers
and software developers. For number theory and graph theory
related terms, we refer to [1] and [4], respectively. For further
study on various graph labeling problems, see [3]. We use
DCL and DCG to denote divisor cordial labeling and divisor
cordial graph, respectively.
Cahit [2] introduced the idea of cordial labeling. Sundaram
et al. [9] coined the notion of prime cordial labeling. The con-
cept of DCL was given by Vartharajan et al. [10]. Vartharajan
et al. [11] proved some general results especially the DCL of
full binary tree.
Definition 1. [10] A DCL of
¯
G having
¯
V is a bijection
¯
f
from
¯
V to {1, 2, 3, ..., |
¯
V |} such that each edge rs is alloted 1 if
¯
f (r)/
¯
f (s) or
¯
f (s)/
¯
f (r) & 0 otherwise, then |e ¯
f
(0) − e ¯
f
(1)|≤
1. If
¯
G admits a DCL, then it is said to be a DCG.
For further results on DCL, refer to [3, 6, 10, 11].
2 Main Results
This section is devoted to derive some general results on
DCG. Also, DCL of lilly graph in the context of different graph
operations has been explored.
2.1 DCL of K
n
Related Graphs
Let N (u) and N [u] represent the open and closed neigh-
bourhood of u, respectively. In this section, we deal with K
n