文献类型：期刊文献

英文题名：The Index of Signed Graphs with Forbidden Subgraphs

作者：Wang, Zhiwen[1,2];Liu, Shuting[3]

机构：[1]East China Univ Sci & Technol, Sch Math, Shanghai 200237, Peoples R China;[2]NanKai Univ, Sch Math Sci, Tianjin 300071, Peoples R China;[3]Shandong Univ Sci & Technol, Coll Math & Syst Sci, Qingdao 266590, Shandong, Peoples R China

年份：2023

卷号：46

期号：5

外文期刊名：BULLETIN OF THE MALAYSIAN MATHEMATICAL SCIENCES SOCIETY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001029971700001)】；

语种：英文

外文关键词：Signed graphs; Index; Extremal graphs; Forbidden subgraphs

摘要：A signed graph Gamma is the graph whose edges get signs +/- 1. The index of Gamma is the largest eigenvalue of its adjacency matrix. For a family F of signed graphs, a signed graph Gamma is said to be F-free if Gamma contains no member in F as its subgraph. The family consisting of all F-free graphs on n vertices is denoted by G(n, F). If F = {F}, we simply write F as F. Let K-n(+) and C-n(+) be the complete graph of order n and cycle of order n whose edges get signs + 1, respectively. In this paper, we, respectively, characterize the extremal graphs possessing the maximum index among G(n, K-s(+)) with s >= 2, G(n, C) with C = {C-l(+) : 3 <= l <= n} and G(n, C-2k) with C-2k = {C-2k(+) : 2 <= k <=[n/2],