拉姆齐良好路径的程度条件

IF 1 3区 数学 Q1 MATHEMATICS European Journal of Combinatorics Pub Date : 2024-10-18 DOI:10.1016/j.ejc.2024.104082
Lucas Aragão , João Pedro Marciano , Walner Mendonça
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引用次数: 0

摘要

Chvátal 的一个经典结果意味着,如果 n≥(r-1)(t-1)+1,那么 Kn 的任何红蓝边着色都包含一个单色红色 Kr 或一个单色蓝色 Pt。我们研究了他的结果的自然推广,确定了 n=(r-1)(t-1)+1 个顶点上的图 G 的精确最小度条件,该条件保证了相同的拉姆齐性质在 G 中成立。特别是,利用哈克赛尔结果的轻微推广,我们证明δ(G)≥n-t/2 就足够了,而且这个约束是最好的。我们还利用 Bollobás、Erdős 和 Straus 的经典结果,证明了在 r=3 的情况下,所有 n≥2t-1 的最小度条件。
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Degree conditions for Ramsey goodness of paths
A classical result of Chvátal implies that if n(r1)(t1)+1, then any colouring of the edges of Kn in red and blue contains either a monochromatic red Kr or a monochromatic blue Pt. We study a natural generalisation of his result, determining the exact minimum degree condition for a graph G on n=(r1)(t1)+1 vertices which guarantees that the same Ramsey property holds in G. In particular, using a slight generalisation of a result of Haxell, we show that δ(G)nt/2 suffices, and that this bound is best possible. We also use a classical result of Bollobás, Erdős, and Straus to prove a tight minimum degree condition in the case r=3 for all n2t1.
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来源期刊
CiteScore
2.10
自引率
10.00%
发文量
124
审稿时长
4-8 weeks
期刊介绍: The European Journal of Combinatorics is a high standard, international, bimonthly journal of pure mathematics, specializing in theories arising from combinatorial problems. The journal is primarily open to papers dealing with mathematical structures within combinatorics and/or establishing direct links between combinatorics and other branches of mathematics and the theories of computing. The journal includes full-length research papers on important topics.
期刊最新文献
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