“…Let A = {k + 2, k + 3,..., n} be an index set and {B, B c } a partition of A, where B = {k + 2, k + 3,..., l + 1} and B c = {l + 2, l + 3,..., n}. Then formally, M n;k,l , 0 ≤ k ≤ l ≤ n -2, can be written, on a 0 -1 sequence , as (see Makri and Psillakis [1]):…”