Number of (n+2)X1 arrays of occupancy after each element moves up to +-n places but not 0.
A222556
Number of (n+2)X1 arrays of occupancy after each element moves up to +-n places but not 0.
Terms
- a(0) =2a(1) =20a(2) =102a(3) =427a(4) =1668a(5) =6372a(6) =24230a(7) =92279a(8) =352596
External references
- oeis: A222556