English

On the size of sets avoiding a general structure

Combinatorics 2025-02-18 v1

Abstract

Given a finite abelian group GG and a subset SGS\subseteq G, we let NG, SN_{G,\ S} be the smallest integer NN such that for any subset AGA\subseteq G with NN elements, we have g+SAg+S\subseteq A for some gGg\in G. Using the probabilistic method, we prove that \begin{align*} \frac{|H_G(S)|-1}{|H_G(S)|}|G|+\Biggl\lceil\biggl(\frac{|G|}{|H_G(S)|}\biggr)^{1-|H_G(S)|/|S|}\Biggr\rceil\le N_{G,\ S}\le \biggl\lfloor\frac{|S|-1}{|S|}|G|\biggr\rfloor+1, \end{align*} where HG(S)H_G(S) is the stabilizer of SS.

Keywords

Cite

@article{arxiv.2409.03222,
  title  = {On the size of sets avoiding a general structure},
  author = {Runze Wang},
  journal= {arXiv preprint arXiv:2409.03222},
  year   = {2025}
}
R2 v1 2026-06-28T18:34:50.797Z