Let G be a finite group, and let r3(G) represent the size of the largest subset of G without non-trivial three-term progressions. In a recent breakthrough, Croot, Lev and Pach proved that r3(C4n) ≤ (3.611)n, where Cm denotes the cyclic group of order m. For finite abelian groups G≅∏i=1nCmi, where m1,…,mn denote positive integers such that m1 |…|mn, this also yields a bound of the form r3(G)⩽(0.903)rk4(G)|G|, with rk4(G) representing the number of indices i ∈ {1,…, n} with 4 |mi. In particular, r3(C8n) ≤ (7.222)n. In this paper, we provide an exponential improvement for this bound, namely r3(C8n) ≤ (7.0899)n.

Original languageEnglish
Pages (from-to)345-363
Number of pages19
JournalIsrael Journal of Mathematics
Volume236
Issue number1
DOIs
StatePublished - 1 Mar 2020

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  • Mathematics(all)

ID: 75248024