Extremal Cactuses for the Schultz and Modified Schultz Indices

Abstract

Let \(G\) be a cactus, where all blocks of \(G\) are either edges or cycles. Denote \(\mathcal{G}(n,r)\) the set of cactuses of order \(n\) and with \(r\) cycles. In this paper, we present a unified approach to the extremal cactuses for the Schultz and the modified Schultz indices.