English

Complete $3$-term arithmetic progression free sets of small size in vector spaces and other abelian groups

Combinatorics 2025-09-30 v4 Number Theory

Abstract

A subset SS of an abelian group GG is called 33-AP\mathrm{AP} free if it does not contain a three term arithmetic progression. Moreover, SS is called complete 33-AP\mathrm{AP} free, if it is maximal w.r.t. set inclusion. One of the most central problems in additive combinatorics is to determine the maximal size of a 33-AP\mathrm{AP} free set, which is necessarily complete. In this paper we are interested in the minimum size of complete 33-AP\mathrm{AP} free sets. We define and study saturation w.r.t. 33-AP\mathrm{AP}s and present constructions of small complete 33-AP\mathrm{AP} free sets and 33-AP\mathrm{AP} saturating sets for several families of vector spaces and cyclic groups.

Keywords

Cite

@article{arxiv.2401.06283,
  title  = {Complete $3$-term arithmetic progression free sets of small size in vector spaces and other abelian groups},
  author = {Bence Csajbók and Zoltán Lóránt Nagy},
  journal= {arXiv preprint arXiv:2401.06283},
  year   = {2025}
}

Comments

Definition 1.8, Proposition 2.3, Theorem 4.14 and Corollary 4.15 are revised