Abstract
Several topological indices and their chemical applicability have been studied in chemical graph theory. Some of the degree based topological indices, namely Zagreb index, Modified Zagreb index, Randi? index, Atom-bond connectivity index, the fourth version of atom-bond connectivity index, Geometric arithmetic index, the fifth version of geometric arithmetic index, Sum connectivity index have been obtained for Cayley tree ??n for k = 2 . In this paper, we have computed these topological indices for the line graph of a Cayley tree L(??n).