T(n,k)=Number of nXk 0..3 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.

A231063

T(n,k)=Number of nXk 0..3 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =2a(5) =0a(6) =0a(7) =6a(8) =6a(9) =0a(10) =0a(11) =20a(12) =34a(13) =20a(14) =0a(15) =0a(16) =68a(17) =208a(18) =208a(19) =68a(20) =0a(21) =0a(22) =230a(23) =1272a(24) =2376a(25) =1272a(26) =230a(27) =0a(28) =0a(29) =778

External references