Computation of Certain Topological Indices of Nanotubes Covered by C ₅ and C ₇

A topological index is a numeric quantity which represents the structure of a graph. A molecular/chemical graph is hydrogen depleted chemical structure in which vertices denote atoms and edges denote the bonds. There are certain types of topological indices like distance based, degree based and counting related topological indices. Among them degree based topological indices are of much importance due to their chemical significance. Carbon nanotubes, a type of fullerene, have potential in fields such as nanotechnology, electronics, optics, materials science and architecture. In this article, we compute atom-bond connectivity (ABC), geometric-arithmetic (GA), Randi c′ and zagreb indices of VC ₅C₇[p, q], HC ₅ C ₇[p, q] and SC ₅ C ₇[p, q] nanotubes. We also compute ABC₄ and GA₅ indices for these nanotubes.