Number of 3Xn 0..3 arrays x(i,j) with each element horizontally 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.

A231109

Number of 3Xn 0..3 arrays x(i,j) with each element horizontally 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) =0a(2) =8a(3) =48a(4) =286a(5) =1748a(6) =10734a(7) =65934a(8) =404984a(9) =2487534a(10) =15279170a(11) =93849326a(12) =576451382a(13) =3540741892a(14) =21748327444a(15) =133584927368a(16) =820519778376

External references