35799856domain: NAppears in sequencesNumber of n X n 0..2 matrices whose square is also a 0..2 matrix.at n=4A213984T(n,k)=Number of n X n 0..k matrices whose square is also a 0..k matrix.at n=19A213990Number of 5X5 0..n matrices whose square is also a 0..n matrix.at n=1A213994