Distance-regular graphs with a1 or c2 at least half the valency

JOURNAL OF COMBINATORIAL THEORY SERIES A

卷:119

Article

Koolen, Jack H.¹  Park, Jongyook² 

[1] POSTECH, Dept Math, Pohang 790785, South Korea

[2] POSTECH, Pohang Math Inst, Pohang 790785, South Korea

关键词: Distance-regular graphs;    Line graphs;    Taylor graphs;   

DOI  :  10.1016/j.jcta.2011.11.001

来源: Elsevier

【 摘 要 】

In this paper, we study the distance-regular graphs Gamma that have a pair of distinct vertices, say x and y. such that the number of common neighbors of x and y is about half the valency of Gamma. We show that if the diameter is at least three, then such a graph, besides a finite number of exceptions, is a Taylor graph, bipartite with diameter three or a line graph. (C) 2011 Elsevier Inc. All rights reserved.

【 授权许可】

Free