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运筹学学报 ›› 2015, Vol. 19 ›› Issue (2): 99-104.doi: 10.15960/j.cnki.issn.1007-6093.2015.02.011

• 运筹学 • 上一篇    下一篇

单圈图和双圈图的最大无符号拉普拉斯分离度

简相国1,袁西英1,*,张曼1   

  1. 1. 上海大学理学院数学系,上海 200444
  • 收稿日期:2014-10-02 出版日期:2015-06-15 发布日期:2015-06-15
  • 通讯作者: 袁西英 xiyingyuan@shu.edu.cn
  • 基金资助:

    国家自然科学基金(No. 11101263)

The maximum signless Laplacian separator of unicyclic and bicyclic graphs

JIAN Xiangguo1,YUAN Xiying1,*,ZHANG Man1   

  1. 1. Department of Mathematics, College of Sciences,Shanghai University, Shanghai 200444, China
  • Received:2014-10-02 Online:2015-06-15 Published:2015-06-15

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1206

被引次数

2

摘要：

设G是一个n阶简单图，q_{1}(G)\geq q_{2}(G)\geq \cdots \geq q_{n}(G)是其无符号拉普拉斯特征值. 图G的无符号拉普拉斯分离度定义为S_{Q}(G)=q_{1}(G)-q_{2}(G). 确定了n阶单圈图和双圈图的最大的无符号拉普拉斯分离度，并分别刻画了相应的极图.

关键词: 单圈图, 双圈图, 无符号拉普拉斯分离度, 无符号拉普拉斯矩阵

Abstract:

Let G be a graph of order n and q_{1}(G)\geq q_{2}(G)\geq \cdots \geq q_{n}(G) be its Q-eigenvalues. The signless Laplacian separator  S_{Q}(G) of G is defined as S_{Q}(G)=q_{1}(G)-q_{2}(G). In this paper, we study the maximum signless Laplacian separator of unicyclic and bicyclic graphs and characterize the extremal graphs, respectively.

Key words: unicyclic graph, bicyclic graph, signless Laplacian separator, signless Laplacian matrix