Ela the Least Eigenvalue of the Signless Laplacian of Non-bipartite Unicyclic Graphs with K Pendant Vertices
نویسنده
چکیده
Let U(n, k) be the set of non-bipartite unicyclic graphs with n vertices and k pendant vertices, where n ≥ 4. In this paper, the unique graph with the minimal least eigenvalue of the signless Laplacian among all graphs in U(n, k) is determined. Furthermore, it is proved that the minimal least eigenvalue of the signless Laplacian is an increasing function in k. Let Un denote the set of non-bipartite unicyclic graphs on n vertices. As an application of the above results, the unique graph with the minimal least eigenvalue of the signless Laplacian among all graphs in Un is characterized, which has recently been proved by Cardoso, Cvetković, Rowlinson, and Simić.
منابع مشابه
The least eigenvalue of the signless Laplacian of non-bipartite unicyclic graphs with k pendant vertices
Let U(n, k) be the set of non-bipartite unicyclic graphs with n vertices and k pendant vertices, where n ≥ 4. In this paper, the unique graph with the minimal least eigenvalue of the signless Laplacian among all graphs in U(n, k) is determined. Furthermore, it is proved that the minimal least eigenvalue of the signless Laplacian is an increasing function in k. Let Un denote the set of non-bipar...
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*Correspondence: [email protected] 1School of Mathematics and Statistics, Yancheng Teachers University, Yancheng, Jiangsu 224002, P.R. China Full list of author information is available at the end of the article Abstract A unicyclic graph is a connected graph whose number of edges is equal to the number of vertices. Fan et al. (Discrete Math. 313:903-909, 2013) and Liu et al. (Electron. J. Linear ...
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