On the eigenvalues of non-commuting graphs

Document Type : Research Paper


Department of Mathematics, Faculty of Science, Shahid Rajaee, Teacher Training University, Tehran, 16785-136, I. R. Iran


The non-commuting graph $\Gamma(G)$ of a non-abelian group $G$ with the center $Z(G)$ is a graph with the
vertex set $V(\Gamma(G))=G\setminus Z(G)$ and two distinct vertices $x$ and $y$ are adjacent in $\Gamma(G)$ if and only if $xy \neq yx$. The aim of this paper is to compute the spectra of some well-known NC-graphs.


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