On a Conjecture Regarding the Exponential Reduced Sombor Index of Chemical Trees

Abstract

Let G be a graph and denote by du the degree of a vertex u of G. The sum of the numbers e √ (du−1)+(dv−1) over all edges uv of G is known as the exponential reduced Sombor index. A chemical tree is a tree with the maximum degree at most 4. In this paper, a conjecture posed by Liu et al. [MATCH Commun. Math. Comput. Chem. 86 (2021) 729–753] is disproved and its corrected version is proved.