T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no 2X2 subblock summing to less than 4.

Terms

a(0) =50a(1) =336a(2) =336a(3) =2167a(4) =5736a(5) =2167a(6) =14180a(7) =91157a(8) =91157a(9) =14180a(10) =92429a(11) =1486258a(12) =3436266a(13) =1486258a(14) =92429a(15) =603249a(16) =24057629a(17) =134840527a(18) =134840527a(19) =24057629a(20) =603249a(21) =3935721a(22) =390354307a(23) =5228522011a(24) =12900566348a(25) =5228522011a(26) =390354307a(27) =3935721