Number of 2 X n 0..3 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.
A231247
Number of 2 X n 0..3 arrays x(i,j) with each element horizontally, diagonally or antidiagonally 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) =2a(2) =14a(3) =44a(4) =146a(5) =572a(6) =2258a(7) =8660a(8) =33026a(9) =126476a(10) =485138a(11) =1859972a(12) =7128386a(13) =27320636a(14) =104717714a(15) =401375924a(16) =1538429186a(17) =5896613228a(18) =22601043602a(19) =86627271908a(20) =332032579394
External references
- oeis: A231247