Some remarks on the sum of the inverse values of the normalized signless Laplacian eigenvalues of graphs

Communications in Combinatorics and Optimization

article

Milovanovic, Igor¹  Milovanovic, Emina¹  Matejic, Marjan¹  Bozkurt Altındağ, Serife Burcu² 

[1] Faculty of Electronic Engineering;Yenikent Kardelen Konutlari

关键词: Normalized Laplacian;    eigenvalues;    bipartite graphs;   

DOI  :  10.22049/cco.2021.26987.1173

学科分类：社会科学、人文和艺术（综合）

来源: Azarbaijan Shahide Madani Universit

【 摘 要 】

Let G = (V, E), V = {v1, v2, . . . , vn}, be a simple connected graph withn vertices, m edges and a sequence of vertex degrees d1 ≥ d2 ≥ · · · ≥ dn > 0,di = d(vi). Let A = (aij )n×n and D = diag(d1, d2, . . . , dn) be the adjacency and thediagonal degree matrix of G, respectively. Denote by L+(G) = D−1/2(D + A)D−1/2the normalized signless Laplacian matrix of graph G. The eigenvalues of matrix L+(G),2 = γ+1 ≥ γ+2 ≥ · · · ≥ γ+n ≥ 0, are normalized signless Laplacian eigenvalues of G. Inthis paper some bounds for the sum K+(G) = Pni=11γ+iare considered.

【 授权许可】

CC BY-SA