The general connectivity indices of fluoranthene-type benzenoid systems

The general connectivity index Rα(G  ) of a graph G=(V,E)G=(V,E) is defined as Rα(G)=∑(u,v)∈E(G)α(dudv),Rα(G)=∑(u,v)∈E(G)(dudv)α, where (u, v) is an edge of G, du and dv denote the degrees of the vertices u and v, respectively, and α ≠ 0 is an arbitrary real number. In this paper, we give the expressions for computing the general connectivity indices of fluoranthene-type benzenoid systems, and we determine the extremal values of Rα(G) in f-benzenoid systems with h hexagons for some real number α. Especially, the extremal values of Rα(G) in cata-catacondensed fluoranthene-type benzenoid systems with h hexagons were studied.