Strengthening topological colorful results for graphs

被引:9
作者
Alishahi, Meysam [1 ]
Hajiabolhassan, Hossein [2 ,3 ]
Meunier, Frederic [4 ]
机构
[1] Shahrood Univ Technol, Sch Math Sci, Shahrood, Iran
[2] Shahid Beheshti Univ, Dept Math Sci, POB 19839-69411, Tehran, Iran
[3] Inst Res Fundamental Sci IPM, Sch Math, POB 19395-5746, Tehran, Iran
[4] Univ Paris Est, CERMICS, F-77455 Marne La Vallee, France
关键词
CIRCULAR CHROMATIC NUMBER; CONJECTURE; PROOF;
D O I
10.1016/j.ejc.2017.03.011
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
Various results ensure the existence of large complete and colorful bipartite graphs in properly colored graphs when some condition related to a topological lower bound on the chromatic number is satisfied. We generalize three theorems of this kind, respectively due to Simonyi and Tardos 2006), Simonyi et al. (2013), and Chen 2011). As a consequence of the generalization of Chen's theorem, we get new families of graphs whose chromatic number equals their circular chromatic number and that satisfy Hedetniemi's conjecture for the circular chromatic number. (c) 2017 Elsevier Ltd. All rights reserved.
引用
收藏
页码:27 / 44
页数:18
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