Number of n X 3 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor.

A221241

Number of n X 3 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor.

Terms

    a(0) =2a(1) =50a(2) =1056a(3) =21660a(4) =441720a(5) =8997120a(6) =183206016a(7) =3730330800a(8) =75953515968

External references