486098916domain: NAppears in sequencesNumber of (n+1) X (3+1) 0..3 arrays with every 2 X 2 subblock summing to a nonzero multiple of 3.at n=5A251338Number of (n+1)X(6+1) 0..3 arrays with every 2X2 subblock summing to a nonzero multiple of 3.at n=2A251341