General sum-connectivity index with \(\alpha\geq1\) for bicyclic graphs. (English) Zbl 1464.05137
Summary: The general sum-connectivity index of a graph \(G\) is a molecular descriptor defined as \(\chi_{\alpha}(G )=\sum_{uv\in E(G)} (d(u )+ d(v))^\alpha\) where, \(d(u)\) denotes the degree of vertex \(u\) in \(G\) and \(\alpha\) is a real number. The aim of this paper is to obtain the graph with the maximum general sum-connectivity index among the connected bicyclic graphs of order \(n\) for \(\alpha \ge 1\).