41623688

Appears in sequences

• Half the number of (n+1)X2 0..3 arrays with no 2X2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one.at n=6A183972
• T(n,k)=Half the number of (n+1)X(k+1) 0..3 arrays with no 2X2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one.at n=21A183976