Ordering the oriented unicyclic graphs whose skew-spectral radius is bounded by 2
نویسندگان
چکیده
*Correspondence: [email protected] 2School of Science, Zhejiang A&F University, Hangzhou, 311300, China Full list of author information is available at the end of the article Abstract Let S(G ) be the skew-adjacency matrix of an oriented graph G with n vertices, and let λ1,λ2, . . . ,λn be all eigenvalues of S(G ). The skew-spectral radius ρs(G ) of G is defined as max{|λ1|, |λ2|, . . . , |λn|}. A connected graph, in which the number of edges equals the number of vertices, is called a unicyclic graph. In this paper, the structure of oriented unicyclic graphs whose skew-spectral radius does not exceed 2 is investigated. We order all the oriented unicyclic graphs with n vertices whose skew-spectral radius is bounded by 2. MSC: 05C50; 15A18
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