T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.

A250536

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.