Non-Bipartite Distance-Regular Graphs with Diameters 5, 6 and a Smallest Eigenvalue

被引：0

作者：

Li, Jing ^{[1
]}

Wang, Yan ^{[2
]}

Hou, Bo ^{[1
]}

Gao, Weidong ^{[3
]}

Gao, Suogang ^{[1
]}

机构：

[1] Hebei Normal Univ, Sch Math Sci, Shijiazhuang 050024, Hebei, Peoples R China

[2] Hebei Univ Econ & Business, Coll Math & Stat, Shijiazhuang 050061, Hebei, Peoples R China

[3] Tianjin Univ, Ctr Appl Math, Tianjin 300072, Peoples R China

来源：

GRAPHS AND COMBINATORICS | 2022年 / 38卷 / 03期

关键词：

Distance-regular graphs; Valancy; Smallest eigenvalue; 2ND LARGEST;

D O I：

10.1007/s00373-022-02458-2

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

Let C be a non-bipartite distance-regular graphs with valancy k, diameter D and a smallest eigenvalue theta(min). In 2019, Qiao, Jing and Koolen classified the non-bipartite distance-regular graphs with theta(min) <= D-1/D k for D = 4; 5. In this paper, we classify the non-bipartite distance-regular graphs with theta(min) <= -D-2/D-1 k for D = 5, 6. We remark that the technique of this paper is an extension of the approach taken by Qiao, Jing and Koolen on the study of non-bipartite distance-regular graphs in 2019.

引用

页数：14

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