Operations Research Transactions ›› 2019, Vol. 23 ›› Issue (1): 81-89.doi: 10.15960/j.cnki.issn.1007-6093.2019.01.009

Previous Articles     Next Articles

On the signless Laplacian spectral radius of tricyclic graphs

CHEN Yuanyuan1, WANG Guoping2,*   

  1. 1. College of Mathematics and System Science, Xinjiang University, Urumqi 830046, China;
    2. School of Mathematical Sciences, Xinjiang Normal University, Urumqi 830046, China
  • Received:2016-12-26 Online:2019-03-15 Published:2019-03-15

Abstract:

Suppose that the vertex set of a graph G is V(G)={v1,v2,…,vn}. Then we denote by dvi(G) the degree of vi in G. Let A(G) be the adjacent matrix of G and D(G) be the n×n diagonal matrix with its (i,i)-entry equal to dvi(G). Then Q(G)=D(G)+A(G) is the signless Laplacian matrix of G. The signless Laplacian spectral radius of G is the largest eigenvalue of Q(G). In this paper we determine the extremal graph with maximum signless Laplacian spectral radius among all tricyclic graphs of order n.

Key words: signless Laplacian spectral radius, tricyclic graph

CLC Number: