T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with all 2X2 subblock sums the same.

Terms

a(0) =81a(1) =171a(2) =171a(3) =361a(4) =309a(5) =361a(6) =855a(7) =579a(8) =579a(9) =855a(10) =2025a(11) =1233a(12) =977a(13) =1233a(14) =2025a(15) =5175a(16) =2691a(17) =1887a(18) =1887a(19) =2691a(20) =5175a(21) =13225a(22) =6417a(23) =3793a(24) =3309a(25) =3793a(26) =6417a(27) =13225a(28) =35535a(29) =15555