a(n) = Sum_{k=0..n} (k! * Stirling2(n,k))^3.

A242280

a(n) = Sum_{k=0..n} (k! * Stirling2(n,k))^3.

Terms

    a(0) =1a(1) =1a(2) =9a(3) =433a(4) =63225a(5) =18954001a(6) =10159366329

External references