English

Gallai-Ramsey numbers for rainbow paths

Combinatorics 2019-02-05 v1

Abstract

Given graphs GG and HH and a positive integer kk, the \emph{Gallai-Ramsey number}, denoted by grk(G:H)gr_{k}(G : H) is defined to be the minimum integer nn such that every coloring of KnK_{n} using at most kk colors will contain either a rainbow copy of GG or a monochromatic copy of HH. We consider this question in the cases where G{P4,P5}G \in \{P_{4}, P_{5}\}. In the case where G=P4G = P_{4}, we completely solve the Gallai-Ramsey question by reducing to the 22-color Ramsey numbers. In the case where G=P5G = P_{5}, we conjecture that the problem reduces to the 33-color Ramsey numbers and provide several results in support of this conjecture.

Keywords

Cite

@article{arxiv.1902.00612,
  title  = {Gallai-Ramsey numbers for rainbow paths},
  author = {Xihe Li and Pierre Besse and Colton Magnant and Ligong Wang and Noah Watts},
  journal= {arXiv preprint arXiv:1902.00612},
  year   = {2019}
}

Comments

20 pages, 2 figures

R2 v1 2026-06-23T07:30:00.107Z