Abstract Given a finite abelian group G and a subset J G J ⊂ G with 0 J 0 ∈ J, let D₆ (J, N) D G (J, N) be the maximum size of A G^N A ⊂ G N such that the difference set A-A A - A and J^N J N have no non-trivial intersection. Recently, this extremal problem has been widely studied for different groups G and subsets J. In this paper, we generalize and improve the relevant results by Alon and by Hegedűs 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 G and J for which the current known upper bounds on D₆ (J, N) D G (J, N) can be improved exponentially.
Xu et al. (Thu,) studied this question.