English

Generalized Ramsey--Tur\'an density for cliques

Combinatorics 2024-03-20 v1

Abstract

We study the generalized Ramsey--Tur\'an function RT(n,Ks,Kt,o(n))\mathrm{RT}(n,K_s,K_t,o(n)), which is the maximum possible number of copies of KsK_s in an nn-vertex KtK_t-free graph with independence number o(n)o(n). The case when s=2s=2 was settled by Erd{\H{o}}s, S{\'o}s, Bollob{\'a}s, Hajnal, and Szemer\'{e}di in the 1980s. We combinatorially resolve the general case for all s3s\ge 3, showing that the (asymptotic) extremal graphs for this problem have simple (bounded) structures. In particular, it implies that the extremal structures follow a periodic pattern when tt is much larger than ss. Our results disprove a conjecture of Balogh, Liu, and Sharifzadeh and show that a relaxed version does hold.

Keywords

Cite

@article{arxiv.2403.12919,
  title  = {Generalized Ramsey--Tur\'an density for cliques},
  author = {Jun Gao and Suyun Jiang and Hong Liu and Maya Sankar},
  journal= {arXiv preprint arXiv:2403.12919},
  year   = {2024}
}

Comments

28 pages

R2 v1 2026-06-28T15:26:03.157Z