Number of n X 4 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, with every occupancy equal to zero or two.
A221274
Number of n X 4 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, with every occupancy equal to zero or two.
Terms
- a(0) =1a(1) =25a(2) =100a(3) =1089a(4) =6724a(5) =56644a(6) =400689a(7) =3122289a(8) =23049601a(9) =175350564a(10) =1311815961a(11) =9905822784a(12) =74413292944a(13) =560619075025
External references
- oeis: A221274