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arXiv · 2009.08177

General cut method for computing Szeged-like topological indices with applications to molecular graphs

Simon Brezovnik·Niko Tratnik
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Abstract

Szeged, PI and Mostar indices are some of the most investigated distance-based molecular descriptors. Recently, many different variations of these topological indices appeared in the literature and sometimes they are all together called Szeged-like topological indices. In this paper, we formally introduce the concept of a general Szeged-like topological index, which includes all mentioned indices and also infinitely many other topological indices that can be defined in a similar way. As the main result of the paper, we provide a cut method for computing a general Szeged-like topological index for any strength-weighted graph. This greatly generalizes various methods known for some of the mentioned indices and therefore rounds off such investigations. Moreover, we provide applications of our main result to benzenoid systems, phenylenes, and coronoid systems, which are well-known families of molecular graphs. In particular, closed-form formulas for some subfamilies of these graphs are deduced.

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Simon Brezovnik, Niko Tratnik. 2020-09-17. General cut method for computing Szeged-like topological indices with applications to molecular graphs. https://doi.org/10.1002/qua.26530

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