maximum matching;
matching number;
Laplacian spectrum;
D O I:
10.1016/S0024-3795(00)00333-5
中图分类号:
O29 [应用数学];
学科分类号:
070104 ;
摘要:
Let G be a graph, its Laplacian matrix is the difference of the diagonal matrix of its vertex degrees and its adjacency matrix. In this paper, we generalize a result in (R. Merris, Port. Math.48 (3) 1991) and obtain the following result: Let G be a graph and M(G) be a maximum matching in G. Then the number of edges in M(G) is a lower bound for the number of Laplacian eigenvalues of G exceeding 2. (C) 2001 Elsevier Science Inc. All rights reserved. AMS classification: 05c50.