Number of 4 X n arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2.

A221331

Number of 4 X n arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2.

Terms

    a(0) =1a(1) =577a(2) =33873a(3) =2460824a(4) =162430981a(5) =10794156688a(6) =711858713069

External references