Bounds on normalized Laplacian eigenvalues of graphs
نویسندگان
چکیده
*Correspondence: [email protected] 1School of Mathematics and Statistics, Minnan Normal University, Zhangzhou, Fujian, P.R. China 2Center for Discrete Mathematics, Fuzhou University, Fuzhou, Fujian, P.R. China Full list of author information is available at the end of the article Abstract Let G be a simple connected graph of order n, where n≥ 2. Its normalized Laplacian eigenvalues are 0 = λ1 ≤ λ2 ≤ · · · ≤ λn ≤ 2. In this paper, some new upper and lower bounds on λn are obtained, respectively. Moreover, connected graphs with λ2 = 1 (or λn–1 = 1) are also characterized. MSC: 05C50; 15A48
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