Further results on centered triangular sum graphs

Let G be a graph with p vertices and q edges. The nth centered triangular number is denoted by M_n, where M_n = 1/2 (3n2 - 3n + 2). A centered triangular sum labeling of a graph G is a one-to-one function : V (G) → N ∪{0} that induces a bijection f *: E(G) →{M_1 〖,M〗_2,…M_q} of the edges of G defined by f * (uv) = f(u) + f(v), for all e = uv ∊ E(G). The graph which admits such labeling is called a centered triangular sum graph. In this article, the centered triangular sum labeling of union of some graphs are studied.