標題: | A characterization of strongly regular graphs in terms of the largest signless Laplacian eigenvalues |
作者: | Fan, Feng-lei Weng, Chih-wen 應用數學系 Department of Applied Mathematics |
關鍵字: | Signless Laplacian matrix;Strongly regular graphs |
公開日期: | 1-十月-2016 |
摘要: | Let G be a simple graph of order n with maximum degree Delta. Let lambda (resp. mu) denote the maximum number of common neighbors of a pair of adjacent vertices (resp. nonadjacent distinct vertices) of G. Let q(G) denote the largest eigenvalue of the signless Laplacian matrix of G. We show that q(G) <= Delta - mu/4 + root(Delta - mu/4)(2) + (1 + lambda)Delta + mu(n - 1) -Delta(2), with equality if and only if G is a strongly regular graph with parameters (n, Delta, lambda, mu). (C) 2016 Elsevier Inc. All rights |
URI: | http://dx.doi.org/10.1016/j.laa.2016.05.009 http://hdl.handle.net/11536/134055 |
ISSN: | 0024-3795 |
DOI: | 10.1016/j.laa.2016.05.009 |
期刊: | LINEAR ALGEBRA AND ITS APPLICATIONS |
Volume: | 506 |
起始頁: | 1 |
結束頁: | 5 |
顯示於類別: | 期刊論文 |