On the adjacency matrix of a threshold graph

被引:32
作者
Bapat, R. B. [1 ]
机构
[1] Indian Stat Inst, Delhi Ctr, New Delhi 110016, India
关键词
Threshold graph; Antiregular graph; Adjacency matrix; Inertia;
D O I
10.1016/j.laa.2013.08.007
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
A threshold graph on n vertices is coded by a binary string of length n - 1. We obtain a formula for the inertia of (the adjacency matrix of) a threshold graph in terms of the code of the graph. It is shown that the number of negative eigenvalues of the adjacency matrix of a threshold graph is the number of ones in the code, whereas the nullity is given by the number of zeros in the code that are preceded by either a zero or a blank. A formula for the determinant of the adjacency matrix of a generalized threshold graph and the inverse, when it exists, of the adjacency matrix of a threshold graph are obtained. Results for antiregular graphs follow as special cases. (C) 2013 Elsevier Inc. All rights reserved.
引用
收藏
页码:3008 / 3015
页数:8
相关论文
共 5 条
[1]  
[Anonymous], 2011, ISRN DISCR MATH, DOI DOI 10.5402/2011/108509
[2]  
Bapat R.B., 2010, Graphs and Matrices, V27
[3]  
Mahadev N.V.R., 1995, ANN DISCRETE MATH, V58
[4]  
Merris R., 2003, Univ. Beograd. Publ. Elektrotehn. Fak. Ser. Mat., V14, P1
[5]  
West D. B., 2006, INTRO GRAPH THEORY