Sombor index of certain graphs

Document Type : Research Paper


1 Department of Informatics, University of Bergen, P.O. Box 7803, 5020 Bergen, Norway

2 Department of Mathematics, Yazd University, 89195-741, Yazd, Iran


Let $G=(V,E)$ be a finite simple graph. The Sombor index $SO(G)$ of $G$ is defined as $\sum_{uv\in E(G)}\sqrt{d_u^2+d_v^2}$, where $d_u$ is the degree of vertex $u$ in $G$. In this paper, we study this index for certain graphs and we examine the effects on $SO(G)$ when $G$ is modified by operations on vertex and edge of $G$. Also we present bounds for the Sombor index of join and corona product of two graphs.



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