Number of nX3 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero.
A230814
Number of nX3 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero.
Terms
- a(0) =0a(1) =2a(2) =4a(3) =12a(4) =100a(5) =326a(6) =2114a(7) =9226a(8) =47220a(9) =233480a(10) =1135788a(11) =5678402a(12) =27785526a(13) =137642146a(14) =678271020a(15) =3346581344a(16) =16519160048a(17) =81474120774a(18) =402103867046
External references
- oeis: A230814