Computing Ga4 Index of an Infinite Class of Nanostar Dendrimers

Abstract

Let G be a connected graph, the GA index (Geometric-Arithmetic index) is a topological index was defined as GA(G)= Sigma(uv is an element of(G))root d(u)d(v)/1/2(d(u)+d(v)) where d(u) denotes degree of u. Now we define a new version of GA index as GA(4)(G)= Sigma(uv is an element of E(G))root epsilon(u)epsilon(v)/1/2(epsilon(u)+epsilon(v)) where epsilon(v) is the largest distance between v and any other vertex u of G or the eccentricity of v. In this paper an exact formula for the GA(4) index of an infinite class of nanostar dendrimers is given.