“…Now, suppose that e ≥ 1. Insert a column vector ( j, j, • • • , j) of length N 2 to the front of the ith column of B to form an N 2 ×k array B j , where j [14]. By Lemma 2.1, we only need to prove that M is a (1, t)-LA, i.e., ρ(M, T 1 ) ρ(M, T 2 ) for any two distinct t-way interactions T 1 and T 2 , where T 1 = {(a 1 , u a 1 ), • • • , (a t , u a t )} and…”