LetG=(V ,E) be a graph, a vertex labeling f : V → Z2 induces an edge labeling f ∗ : E → Z2 defined by f ∗(xy)=f (x)+f (y) for each xy ∈ E. For each i ∈ Z2, define vf (i)=|f−1(i)| and ef (i)=|f ∗−1(i)|. We call f friendly if |vf (1)− vf (0)| 1. The full friendly index set of G is the set of all possible values of ef (1)− ef (0), where f is friendly. In this note, we study the full friendly index...

An antimagic labeling of a connected graph with m edges is an injective assignment of labels from {1, . . . , m} to the edges such that the sums of incident labels are distinct at distinct vertices. Hartsfield and Ringel conjectured that every connected graph other than K2 has an antimagic labeling. We prove this for the classes of split graphs and graphs decomposable under the canonical decomp...

Let G = (V,E) be a graph of order n. A bijection f : V → {1, 2, . . . , n} is called a distance magic labeling of G if there exists a positive integer k such that ∑ u∈N(v) f(u) = k for all v ∈ V, where N(v) is the open neighborhood of v. The constant k is called the magic constant of the labeling f . Any graph which admits a distance magic labeling is called a distance magic graph. In this pape...

Abstract In this paper we define some new labellings for trees, called the in-improper and out-improper odd-graceful labellings such that some trees labelled with the new labellings can induce graceful graphs having at least a cycle. We, next, apply the new labellings to construct large scale of graphs having improper graceful/odd-graceful labellings or having graceful/odd-graceful labellings.

An injective function f : V (G)→ {0, 1, 2, . . . , q} is an odd sum labeling if the induced edge labeling f∗ defined by f∗(uv) = f(u) + f(v), for all uv ∈ E(G), is bijective and f∗(E(G)) = {1, 3, 5, . . . , 2q − 1}. A graph is said to be an odd sum graph if it admits an odd sum labeling. In this paper, we have studied the odd sum property of the subdivision of the triangular snake, quadrilatera...

An L(2, 1)-labeling of a graph G is equitable if the number of elements in any two color classes differ by at most one. The equitable L(2, 1)-labeling number λe(G) of G is the smallest integer k such that G has an equitable L(2, 1)-labeling. Sierpiński graphs S(n, k) generalize the Tower of Hanoi graphs—the graph S(n, 3) is isomorphic to the graph of the Tower of Hanoi with n disks. In this pap...

Let G be a (p, q) graph. Let f : V (G) → {1, 2 . . . , p} be a function. For each edge uv, assign the label |f (u)− f (v)|. f is called a difference cordial labeling if f is a one to one map and |ef (0)− ef (1)| ≤ 1 where ef (1) and ef (0) denote the number of edges labeled with 1 and not labeled with 1 respectively. A graph with a difference cordial labeling is called a difference cordial grap...

Let d(u, v) denote the distance between two distinct vertices of a connected graph G, and diam(G) be the diameter of G. A radio labeling c of G is an assignment of positive integers to the vertices ofG satisfying d(u, v)+|c(u)−c(v)| ≥ diam(G)+1 for every two distinct vertices u, v. The maximum integer in the range of the labeling is its span. The radio number of G, rn(G), is the minimum possibl...

An edge labeling of a graph G = (V,E) is a bijection from the set of edges to the set of integers {1, 2, . . . , |E|}. The weight of a vertex v is the sum of the labels of all the edges incident with v. If the vertex weights are all distinct then we say that the labeling is vertex-antimagic, or simply, antimagic. A graph that admits an antimagic labeling is called an antimagic graph. In this pa...

Let be a connected graph with vertex set and edge . A bijection from to the is labeling of The called rainbow antimagic if for any two in path , where Rainbow coloring which has labeling. Thus, every induces G weight color connection number smallest colors all colorings denoted by In this study, we studied have an exact value joint product