T(n,k)=Number of nXk 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

A229847

T(n,k)=Number of nXk 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

Terms

    a(0) =0a(1) =3a(2) =3a(3) =3a(4) =15a(5) =3a(6) =9a(7) =81a(8) =81a(9) =9a(10) =15a(11) =423a(12) =987a(13) =423a(14) =15a(15) =33a(16) =2247a(17) =13401a(18) =13401a(19) =2247a(20) =33a(21) =63a(22) =11925a(23) =178311a(24) =453837a(25) =178311a(26) =11925a(27) =63a(28) =129a(29) =63291

External references