Operations Research Transactions ›› 2019, Vol. 23 ›› Issue (1): 72-80.doi: 10.15960/j.cnki.issn.1007-6093.2019.01.008

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Laplacian spectral characterizations of new unicyclic graphs H(p,tK1,m)

SUN Qiushi, YANG Xiaoyun, WANG Ligong*, LI Xihe, WANG Pengchao   

  1. Department of Applied Mathematics, School of Science, Northwestern Polytechnical University, Xi'an 710072, China
  • Received:2017-02-09 Online:2019-03-15 Published:2019-03-15

Abstract:

Let H(p,tK1,m) denote an unicyclic graph with p+mt vertices obtained from Cp by attaching the center of star K1,m to each one of t mutual adjacent vertices of the cycle Cp, respectively. In this paper, we show that the unicyclic graphs H(p,p K1,5) and H((p,(p-1)K1,4) are determined by their Laplacian spectra, and if p is an even number, then the unicyclic graphs H(p, 2K1,4), H(p,(p-2)K1,4) and H(p,(p-3)K1,4) are also determined by their Laplacian spectra.

Key words: Laplacian matrix, determined by Laplacian spectrum, unicyclic graph

CLC Number: