Numerator of Sum_{k=1..n} n^(k-1)/k!.

Terms

a(0) =1a(1) =2a(2) =4a(3) =25a(4) =217a(5) =203a(6) =6743a(7) =69511a(8) =1184417a(9) =728102a(10) =5720654791a(11) =601499a(13) =42568060798a(14) =888330615353