English

Stars versus stripes Ramsey numbers

Combinatorics 2017-01-17 v1

Abstract

For given simple graphs G1,G2,,GtG_1, G_2, \ldots , G_t, the Ramsey number R(G1,G2,,Gt)R(G_1, G_2, \ldots, G_t) is the smallest positive integer nn such that if the edges of the complete graph KnK_n are partitioned into tt disjoint color classes giving tt graphs H1,H2,,HtH_1,H_2,\ldots,H_t, then at least one HiH_i has a subgraph isomorphic to GiG_i. In this paper, for positive integers t1,t2,,tst_1,t_2,\ldots, t_s and n1,n2,,ncn_1,n_2,\ldots, n_c the Ramsey number R(St1,St2,,Sts,n1K2,n2K2,,ncK2)R(S_{t_1}, S_{t_2},\ldots ,S_{t_s}, n_1K_2,n_2K_2,\ldots,n_cK_2) is computed, where nK2nK_2 denotes a matching (stripe) of size nn, i.e., nn pairwise disjoint edges and SnS_{n} is a star with nn edges. This result generalizes and strengthens significantly a well-known result of Cockayne and Lorimer and also a known result of Gy\'{a}rf\'{a}s and S\'{a}rk\"{o}zy.

Keywords

Cite

@article{arxiv.1701.04191,
  title  = {Stars versus stripes Ramsey numbers},
  author = {G. R. Omidi and G. Raeisi and Z. Rahimi},
  journal= {arXiv preprint arXiv:1701.04191},
  year   = {2017}
}
R2 v1 2026-06-22T17:50:54.343Z