Characterizing threshold graphs with k main signless Laplacian eigenvalues

被引:3
作者
Vinagre, Cybele T. M. [1 ]
Trevisan, Vilmar [2 ]
Bolckau, Johann [1 ]
Chimelli, Rodrigo [1 ]
机构
[1] Univ Fed Fluminense, Inst Matemat & Estat, Niteroi, RJ, Brazil
[2] Univ Fed Rio Grande do Sul, Inst Matemat, Porto Alegre, RS, Brazil
关键词
Signless Laplacian matrix; Main eigenvalue; Threshold graph; BICYCLIC GRAPHS; MATRICES;
D O I
10.1016/j.laa.2020.04.022
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We show that the number k of main signless Laplacian eigenvalues of a threshold graph on n >= 3 vertices is bounded by n - 2 and we characterize, for any integer 1 <= k <= n - 2, all such graphs with exactly k main signless Laplacian eigenvalues. Moreover, we also determine the number of threshold graphs on n vertices with k main signless Laplacian eigenvalues. (C) 2020 Elsevier Inc. All rights reserved.
引用
收藏
页码:33 / 45
页数:13
相关论文
共 20 条
[1]   Fast algorithms for computing the characteristic polynomial of threshold and chain graphs [J].
Andelic, M. ;
Simic, S. K. ;
Zivkovic, D. ;
Dolicanin, E. C. .
APPLIED MATHEMATICS AND COMPUTATION, 2018, 332 :329-337
[2]  
[Anonymous], 2011, ISRN DISCR MATH, DOI DOI 10.5402/2011/108509
[3]  
[Anonymous], 1977, Ann. Discrete Math.
[4]   Spectra, signless Laplacian and Laplacian spectra of complementary prisms of graphs [J].
Cardoso, Domingos M. ;
Carvalho, Paula ;
de Freitas, Maria Aguieiras A. ;
Vinagre, Cybele T. M. .
LINEAR ALGEBRA AND ITS APPLICATIONS, 2018, 544 :325-338
[5]   Exponentially many graphs have a Q-cospectral mate [J].
Carvalho, Joao ;
Souza, Bruna S. ;
Trevisan, Vilmar ;
Tura, Fernando C. .
DISCRETE MATHEMATICS, 2017, 340 (09) :2079-2085
[6]   Trees, Unicyclic Graphs and Bicyclic Graphs with Exactly Two Q-main Eigenvalues [J].
Chen, Lin ;
Huang, Qiong Xiang .
ACTA MATHEMATICA SINICA-ENGLISH SERIES, 2013, 29 (11) :2193-2208
[7]  
Cvetkovic D., PUBL I MATH BEOGRAD, V85
[8]  
Cvetkovic D.M., 1970, PUBL ELEKTROTEH FAK, V320, P27
[9]  
Cvetkovic D. M., 1971, Publ. Elektroteh. Fak. Univ. Beogr. Ser. Mat. Fiz., V354, P1
[10]   Signless Laplacians of finite graphs [J].
Cvetkovic, Dragos ;
Rowlinson, Peter ;
Simic, Slobodan K. .
LINEAR ALGEBRA AND ITS APPLICATIONS, 2007, 423 (01) :155-171