a(n) = Sum_{k=1..n} (-1)^(n-k) * Stirling1(n,k) * (k-1)! * sigma(k), where sigma = A000203.
A330494
a(n) = Sum_{k=1..n} (-1)^(n-k) * Stirling1(n,k) * (k-1)! * sigma(k), where sigma = A000203.
Terms
- a(0) =1a(1) =4a(2) =19a(3) =129a(4) =1018a(5) =9912a(6) =111074a(7) =1416398a(8) =20295208a(9) =323437728a(10) =5657339928a(11) =107765338920
External references
- oeis: A330494