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arXiv · 2108.08552

On the Sombor characteristic polynomial and Sombor energy of a graph

Abstract

Let $G$ be a simple graph with vertex set $V(G) = \{v_1, v_2,\ldots, v_n\}$. The Sombor matrix of $G$, denoted by $A_{SO}(G)$, is defined as the $n\times n$ matrix whose $(i,j)$-entry is $\sqrt{d_i^2+d_j^2}$ if $v_i$ and $v_j$ are adjacent and $0$ for another cases. Let the eigenvalues of the Sombor matrix $A_{SO}(G)$ be $ρ_1\geq ρ_2\geq \ldots\geq ρ_n$ which are the roots of the Sombor characteristic polynomial $\prod_{i=1}^n (ρ-ρ_i)$. The Sombor energy $En_{SO}$ of $G$ is the sum of absolute values of the eigenvalues of $A_{SO}(G)$. In this paper we compute the Sombor characteristic polynomial and the Sombor energy for some graph classes, define Sombor energy unique and propose a conjecture on Sombor Energy.

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Nima Ghanbari. 2021-08-19. On the Sombor characteristic polynomial and Sombor energy of a graph. https://arxiv.org/abs/2108.08552

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