E.g.f. (1+x)^(x+x^2).

Terms

a(0) =1a(1) =0a(2) =2a(3) =3a(4) =8a(5) =70a(6) =54a(7) =1428a(8) =2624a(9) =27144a(10) =158040a(11) =653400a(12) =6245832a(13) =48636432a(14) =-32399472a(15) =6915245400a(16) =-59561508480