Expansion of e.g.f. (1 + x * (exp(x) - 1))^3.

Terms

a(0) =1a(1) =0a(2) =6a(3) =9a(4) =84a(5) =375a(6) =1998a(7) =11361a(8) =60840a(9) =299403a(10) =1368930a(11) =5906373a(12) =24362748a(13) =97019247a(14) =375712470a(15) =1422455625a(16) =5286155088a(17) =19340722707a(18) =69831127242a(19) =249265052301a(20) =880927979940