Intersective sets over abelian groups
Combinatorics
2026-01-06 v3 Number Theory
Abstract
Given a finite abelian group and a subset with , let be the maximum size of such that the difference set and have no non-trivial intersection. Recently, this extremal problem has been widely studied for different groups and subsets . In this paper, we generalize and improve the relevant results by Alon and by Heged\H{u}s by building a bridge between this problem and cyclotomic polynomials with the help of algebraic graph theory. In particular, we construct infinitely many non-trivial families of and for which the current known upper bounds on can be improved exponentially.
Cite
@article{arxiv.2207.00053,
title = {Intersective sets over abelian groups},
author = {Zixiang Xu and Chi Hoi Yip},
journal= {arXiv preprint arXiv:2207.00053},
year = {2026}
}
Comments
17 pages, revised based on referee comments