The chromatic index of strongly regular graphs

被引:3
作者
Cioaba, Sebastian M. [1 ]
Guo, Krystal [2 ]
Haemers, Willem H. [3 ]
机构
[1] Univ Delaware, Dept Math Sci, Newark, DE 19716 USA
[2] Univ Amsterdam, Korteweg De Vries Inst, Amsterdam, Netherlands
[3] Tilburg Univ, Dept Econometr & Operat Res, Tilburg, Netherlands
关键词
Strongly regular graph; chromatic index; edge coloring; 1-factorization; PETERSEN GRAPH; 1-FACTORIZATION;
D O I
10.26493/1855-3974.2435.3db
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We determine (partly by computer search) the chromatic index (edge-chromatic number) of many strongly regular graphs (SRGs), including the SRGs of degree k <= 18 and their complements, the Latin square graphs and their complements, and the triangular graphs and their complements. Moreover, using a recent result of Ferber and Jain, we prove that an SRG of even order n, which is not the block graph of a Steiner 2-design or its complement, has chromatic index k, when n is big enough. Except for the Petersen graph, all investigated connected SRGs of even order have chromatic index equal to k, i.e., they are class 1, and we conjecture that this is the case for all connected SRGs of even order.
引用
收藏
页码:187 / 194
页数:8
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