a(n) is the number of permutations pi on n letters such that pi(i) != i (mod 3) for all i.
A340900
a(n) is the number of permutations pi on n letters such that pi(i) != i (mod 3) for all i.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =2a(4) =4a(5) =16a(6) =80a(7) =288a(8) =1728a(9) =12096a(10) =67392a(11) =525312a(12) =4783104a(13) =35942400a(14) =349056000a(15) =3891456000a(16) =36910080000a(17) =429981696000
External references
- oeis: A340900