General approach for obtaining extremal results on degree-based indices illustrated on the general sum-connectivity index

Tomáš Vetrík

Abstract


Among bipartite graphs with given order and matching number/vertex cover number/edge cover number/independence number, among multipartite graphs with given order, and among graphs with given order and chromatic number, we present the graphs having the maximum degree-based index if that index satisfies certain conditions. We show that those conditions are satisfied by the general sum-connectivity index χa for all or some a ≥ 0.

 

Keywords


general sum-connectivity index; topological index; extremal graph

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DOI: http://dx.doi.org/10.5614/ejgta.2023.11.1.10

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