a(n) = (n-1)! * Sum_{d|n} d/(d-1)!.

Terms

a(0) =1a(1) =3a(2) =5a(3) =22a(4) =29a(5) =546a(6) =727a(7) =18488a(8) =100809a(9) =1164250a(10) =3628811a(11) =208232652a(12) =479001613a(13) =18741602894a(14) =236107872015