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On the signless Laplacian spectral radius of graphs with cut vertices

โœ Scribed by Bao-Xuan Zhu


Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
129 KB
Volume
433
Category
Article
ISSN
0024-3795

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โœฆ Synopsis


In this paper, we show that among all the connected graphs with n vertices and k cut vertices, the maximal signless Laplacian spectral radius is attained uniquely at the graph G n,k , where G n,k is obtained from the complete graph K n-k by attaching paths of almost equal lengths to all vertices of K n-k . We also give a new proof of the analogous result for the spectral radius of the connected graphs with n vertices and k cut vertices (see [A. Berman, X.-D. Zhang, On the spectral radius of graphs with cut vertices, J. Combin. Theory Ser. B 83 (2001) 233-240]). Finally, we discuss the limit point of the maximal signless Laplacian spectral radius.


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