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Some results on the signless Laplacians of graphs

✍ Scribed by Jianfeng Wang; Qiongxiang Huang; Xinhui An; Francesco Belardo

Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
277 KB
Volume
23
Category
Article
ISSN
0893-9659

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✦ Synopsis

In this paper we give two results concerning the signless Laplacian spectra of simple graphs. Firstly, we give a combinatorial expression for the fourth coefficient of the (signless Laplacian) characteristic polynomial of a graph. Secondly, we consider limit points for the (signless Laplacian) eigenvalues and we prove that each non-negative real number is a limit point for (signless Laplacian) eigenvalue of graphs.

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