English

Supersaturation for hereditary properties

Combinatorics 2011-04-29 v1

Abstract

Let F\mathcal{F} be a collection of rr-uniform hypergraphs, and let 0<p<10 < p < 1. It is known that there exists c=c(p,F)c = c(p,\mathcal{F}) such that the probability of a random rr-graph in G(n,p)G(n,p) not containing an induced subgraph from F\mathcal{F} is 2(c+o(1))(nr)2^{(-c+o(1)){n \choose r}}. Let each graph in F\mathcal{F} have at least tt vertices. We show that in fact for every ϵ>0\epsilon > 0, there exists δ=δ(ϵ,p,F)>0\delta = \delta (\epsilon, p,\mathcal{F}) > 0 such that the probability of a random rr-graph in G(n,p)G(n,p) containing less than δnt\delta n^t induced subgraphs each lying in F\mathcal{F} is at most 2(c+ϵ)(nr)2^{(-c+\epsilon){n \choose r}}. This statement is an analogue for hereditary properties of the supersaturation theorem of Erd\H{o}s and Simonovits. In our applications we answer a question of Bollob\'as and Nikiforov.

Keywords

Cite

@article{arxiv.1104.5401,
  title  = {Supersaturation for hereditary properties},
  author = {David Saxton},
  journal= {arXiv preprint arXiv:1104.5401},
  year   = {2011}
}

Comments

5 pages, submitted to European Journal of Combinatorics

R2 v1 2026-06-21T17:59:52.825Z