Number of nX4 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without move-in move-out straight through or left turns.
A221751
Number of nX4 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without move-in move-out straight through or left turns.
Terms
- a(0) =1a(1) =9a(2) =43a(3) =241a(4) =1397a(5) =7989a(6) =45956a(7) =264378a(8) =1520571a(9) =8746983a(10) =50315631a(11) =289432219a(12) =1664916443a(13) =9577180972a(14) =55091295173a(15) =316904423483
External references
- oeis: A221751