Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without move-in move-out straight through or left turns.
A221940
Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without move-in move-out straight through or left turns.
Terms
- a(0) =1a(1) =489a(2) =24535a(3) =1759041a(4) =119035112a(5) =8118923949a(6) =552777330287
External references
- oeis: A221940