Number of n X 4 arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.

A221122

Number of n X 4 arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.

Terms

    a(0) =21a(1) =1950a(2) =179300a(3) =16436223a(4) =1506094707a(5) =138001217828

External references