a(n) = Sum_{k=0..n} (k+1)^4 * Stirling2(n,k).

Terms

a(0) =1a(1) =16a(2) =97a(3) =515a(4) =2744a(5) =15177a(6) =88033a(7) =536882a(8) =3441439a(9) =23151411a(10) =163135410a(11) =1201594675a(12) =9232595661a(13) =73858810120a(14) =614045917741