摘要

Motivated by the equivalent conditions for the inclusions
A(n){1,2,i}...A(2){1,2,i}A(1){1,2,i} subset of (A(1)A(2)...A(n)){1,2,i} (i = 3,4)
presented in [B. Zheng and Z. Xiong. The reverse order laws for {1,2,3}- and {1,2,4}-inverses of multiple matrix products. Linear Multilinear Algebra, 58:765-782, 2010.], we show that for i is an element of {3,4},
A(n){1,2,i}...A(2){1,2,i}A(1){1,2,i} = (A(1)A(2)...A(n)){1,2,i}
is equivalent to
A(n){1,2,i}...A(2){1, 2,i}A(1){1,2,i} subset of (A(1)A(2)...A(n)){1,2,i}.