Krein parameters and antipodal tight graphs with diameter 3 and 4

被引：30

作者：

Jurisic, A

Koolen, J

机构：

[1] IMFM, Nova Gorica, Slovenia

[2] Nova Gorica Polytech, Nova Gorica, Slovenia

[3] Univ Bielefeld, FSP, D-33501 Bielefeld, Germany

来源：

DISCRETE MATHEMATICS | 2002年 / 244卷 / 1-3期

关键词：

Krein parameters; distance-regular graphs; tight graphs; 1-homogeneous graphs; antipodal graphs; locally strongly-regular; Taylor graphs;

D O I：

10.1016/S0012-365X(01)00082-6

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

We determine which Krein parameters of nonbipartite antipodal distance-regular graphs of diameter 3 and 4 can vanish, and give combinatorial interpretations of their vanishing. We also study tight distance-regular graphs of diameter 3 and 4. In the case of diameter 3, tight graphs are precisely the Taylor graphs. In the case of antipodal distance-regular graphs of diameter 4, tight graphs are precisely the graphs for which the Krein parameter q(11)(4) vanishes. (C) 2002 Elsevier Science B.V. All rights reserved.

引用

页码：181 / 202

页数：22

共 32 条

[1] Distance-regular graphs with b(2)=1 and antipodal covers [J].