a(n) = n! * Sum_{d|n} binomial(n-1,d-1) / d!.
A329966
a(n) = n! * Sum_{d|n} binomial(n-1,d-1) / d!.
Terms
- a(0) =1a(1) =3a(2) =7a(3) =61a(4) =121a(5) =3721a(6) =5041a(7) =240241a(8) =2056321a(9) =23768641a(10) =39916801a(11) =11104853761a(12) =6227020801a(13) =683519316481
External references
- oeis: A329966