223164domain: NAppears in sequencesNumber of (n+1)X(3+1) 0..3 arrays with every 2X2 subblock summing to 3 6 or 9.at n=2A251295T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock summing to 3 6 or 9.at n=12A251300