Expansion of e.g.f. x*exp(x)*exp(x*exp(x)).

Terms

a(0) =0a(1) =1a(2) =4a(3) =18a(4) =92a(5) =520a(6) =3222a(7) =21700a(8) =157544a(9) =1224576a(10) =10133450a(11) =88843084a(12) =821832156a(13) =7992373168a(14) =81458868974a(15) =867700216380