6775415354domain: 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=6A251338Number of (n+1)X(7+1) 0..3 arrays with every 2X2 subblock summing to a nonzero multiple of 3.at n=2A251342