English

Ramsey numbers of $4$-uniform loose cycles

Combinatorics 2016-06-14 v2

Abstract

Gy\'arf\'as, S\'ark\"ozy and Szemer\'edi proved that the 22-color Ramsey number R(Cnk,Cnk)R(\mathcal{C}^k_n,\mathcal{C}^k_n) of a kk-uniform loose cycle Cnk\mathcal{C}^k_n is asymptotically 12(2k1)n,\frac{1}{2}(2k-1)n, generating the same result for k=3k=3 due to Haxell et al. Concerning their results, it is conjectured that for every nm3n\geq m\geq 3 and k3,k\geq 3, R(Cnk,Cmk)=(k1)n+m12.R(\mathcal{C}^k_n,\mathcal{C}^k_m)=(k-1)n+\lfloor\frac{m-1}{2}\rfloor. In 20142014, the case k=3k=3 is proved by the authors. Recently, the authors showed that this conjecture is true for n=m2n=m\geq 2 and k8k\geq 8. In this paper, we show that the conjecture holds for k=4k=4 when n>mn>m or n=mn=m is odd. When n=mn=m is even, we show that R(Cn4,Cn4)R(\mathcal{C}^4_n,\mathcal{C}^4_n) is between two values with difference one.

Keywords

Cite

@article{arxiv.1603.01697,
  title  = {Ramsey numbers of $4$-uniform loose cycles},
  author = {Gholamreza Omidi and Maryam Shahsiah},
  journal= {arXiv preprint arXiv:1603.01697},
  year   = {2016}
}

Comments

arXiv admin note: substantial text overlap with arXiv:1602.05386