English

Generalizations of the Ruzsa-Szemer\'edi and rainbow Tur\'an problems for cliques

Combinatorics 2022-02-28 v2

Abstract

Considering a natural generalization of the Ruzsa-Szemer\'edi problem, we prove that for any fixed positive integers r,sr,s with r<sr<s, there are graphs on nn vertices containing nreO(logn)=nro(1)n^{r}e^{-O(\sqrt{\log{n}})}=n^{r-o(1)} copies of KsK_s such that any KrK_r is contained in at most one KsK_s. We also give bounds for the generalized rainbow Tur\'an problem ex(n,H,\operatorname{ex}(n, H,rainbow-F)F) when FF is complete. In particular, we answer a question of Gerbner, M\'esz\'aros, Methuku and Palmer, showing that there are properly edge-coloured graphs on nn vertices with nr1o(1)n^{r-1-o(1)} copies of KrK_r such that no KrK_r is rainbow.

Keywords

Cite

@article{arxiv.2003.02754,
  title  = {Generalizations of the Ruzsa-Szemer\'edi and rainbow Tur\'an problems for cliques},
  author = {W. T. Gowers and Barnabás Janzer},
  journal= {arXiv preprint arXiv:2003.02754},
  year   = {2022}
}

Comments

19 pages, 1 figure. Minor changes in Subsection 5.1 compared to the first version