On strongly regular graphs with eigenvalue μ and their extensions

被引:6
作者
Makhnev, A. A. [1 ,2 ]
Paduchikh, D. V. [1 ]
机构
[1] Russian Acad Sci, Ural Branch, Inst Math & Mech, Ekaterinburg 620990, Russia
[2] Ural Fed Univ, Inst Radioelect & Informat Technol, Ekaterinburg 620002, Russia
基金
俄罗斯基础研究基金会; 中国国家自然科学基金;
关键词
strongly regular graph; AT4-graph; locally M-graph;
D O I
10.1134/S0081543814050137
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
Let M be a class of strongly regular graphs for which mu is a nonprincipal eigenvalue. Note that the neighborhood of any vertex of an AT4-graph lies in M. We describe parameters of graphs from M and find intersection arrays of AT4-graphs in which neighborhoods of vertices lie in chosen subclasses from M. In particular, an AT4-graph in which neighborhoods of vertices do not contain triangles is the Conway-Smith graph with parameters (p, q, r) = (1, 2, 3) or the first Soicher graph with parameters (p, q, r) = (2, 4, 3).
引用
收藏
页码:S128 / S135
页数:8
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