a(n) = n! * Sum_{k=1..n} Sum_{d|k} 1/(d * ((k/d)!)^d).
A356407
a(n) = n! * Sum_{k=1..n} Sum_{d|k} 1/(d * ((k/d)!)^d).
Terms
- a(0) =1a(1) =4a(2) =15a(3) =70a(4) =375a(5) =2411a(6) =17598a(7) =146490a(8) =1359291a(9) =13978597a(10) =157393368a(11) =1929989029a(12) =25568858978a(13) =364288345409
External references
- oeis: A356407