Abstract:
In article we study the multiplicative property of set residue mod n. Given a natural
number n, every set of residues mod n of cardinality at least n/2 contains residues
a, b, c with ab = c. The set is said to be a product free if ab = c has no solution with
abc ∈ S. We say a modulus n having property P if the largest product-free subset
S of Zn has cardinality strictly smaller than n/2.
