a(n) = n! * Sum_{k=1..n} ( Sum_{d|k} 1/(d * (k/d)!) )/(n-k)!.
A354338
a(n) = n! * Sum_{k=1..n} ( Sum_{d|k} 1/(d * (k/d)!) )/(n-k)!.
Terms
- a(0) =1a(1) =4a(2) =12a(3) =41a(4) =145a(5) =742a(6) =3962a(7) =27659a(8) =215131a(9) =1996356a(10) =17300360a(11) =218809109a(12) =2421142269a(13) =31105286682a(14) =427776526574
External references
- oeis: A354338