On Eigenvalues of Permutation Graphs

Document Type : Original Scientific Paper


Department of Mathematics, Faculty of Basic Sciences, Islamic Azad University, Central Tehran Branch, Tehran, Iran


Let λ1(G), λ2(G),..., λs(G) be the distinct eigenvalues of G with multiplicities t1, t2,..., ts, respectively. The multiset {λ1(G)t1, λ2(G)t2,..., λs(G)ts} of eigenvalues of A(G) is called the spectrum of G. For two graphs G and H, if their spectrum are the same, then G and H are said to be co-spectral. The aim of this paper is to determine co-spectral permutation graphs with respect to automorphism group of graph G.


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