Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.

A267620

Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.

Terms

    a(0) =0a(1) =6a(2) =48a(3) =906a(4) =59328a(5) =2192682a(6) =131218206a(7) =6966218352a(8) =394140187926

External references