a(n) = Sum_{k=0..n} Stirling2(n,k)*Stirling2(n+1,k+1)*k!.
A192557
a(n) = Sum_{k=0..n} Stirling2(n,k)*Stirling2(n+1,k+1)*k!.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =49a(4) =749a(5) =16201a(6) =464645a(7) =16911049a(8) =756570029a(9) =40608430681
External references
- oeis: A192557