a(n) = Sum_{k=0..floor(n/4)} (-1)^k * (n-4*k)!.
A358609
a(n) = Sum_{k=0..floor(n/4)} (-1)^k * (n-4*k)!.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =23a(5) =119a(6) =718a(7) =5034a(8) =40297a(9) =362761a(10) =3628082a(11) =39911766a(12) =478961303a(13) =6226658039a(14) =87174663118
External references
- oeis: A358609