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

A217268

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

Terms

    a(0) =2a(1) =64a(2) =1472a(3) =33856a(4) =772800a(5) =17640000a(6) =402494400a(7) =9183772224a(8) =209543184576

External references