EXTREMAL TETRACYCLIC GRAPHS WITH RESPECT TO THE FIRST an‎d SECOND ZAGREB INDICES

The rst Zagreb index, M1(G), and second Zagreb index, M2(G), of the graph G is dened as M1(G) = Σ v2V (G) d2(v) and M2(G) = Σ e=uv2E(G) d(u)d(v); where d(u) denotes the degree of vertex u. In this paper, the rst and second maximum values of the rst and second Zagreb indices in the class of all n􀀀vertex tetracyclic graphs are presented