T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock summing to 4 5 6 7 or 8.

A251499

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock summing to 4 5 6 7 or 8.

Terms

    a(0) =186a(1) =2270a(2) =2270a(3) =27844a(4) =86946a(5) =27844a(6) =341718a(7) =3361296a(8) =3361296a(9) =341718a(10) =4194002a(11) =130169514a(12) =411510096a(13) =130169514a(14) =4194002a(15) =51474508a(16) =5042543734a(17) =50511532876a(18) =50511532876a(19) =5042543734a(20) =51474508a(21) =631765770a(22) =195351371872

External references