Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor.

A220999

Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor.

Terms

    a(0) =21a(1) =2989a(2) =394580a(3) =51672851a(4) =6758547145a(5) =883809591160

External references