Let m ≥ 2 and n ≥ 1. A ring R is called a T(m, n)-ring if for every m n-subsets A1,A2, . . . , Am of R there exist i = j and xi ∈ Ai, xj 20 ∈ Aj such that [xi, xj ] = 0.We give 21 noncommutative examples of such rings, and we discuss finiteness and commutativity.
