a(n) = n! * Sum_{k=1..n} ( Sum_{d|k} (-1)^(k/d+1) * d^2 )/(k * (n-k)!).
A354508
a(n) = n! * Sum_{k=1..n} ( Sum_{d|k} (-1)^(k/d+1) * d^2 )/(k * (n-k)!).
Terms
- a(0) =1a(1) =5a(2) =32a(3) =168a(4) =1189a(5) =8785a(6) =77384a(7) =646296a(8) =7306737a(9) =79997893a(10) =1005481784a(11) =12518370128a(12) =184109233125
External references
- oeis: A354508