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

Terms

a(0) =1a(1) =4a(2) =18a(3) =91a(4) =512a(5) =3169a(6) =21352a(7) =155257a(8) =1209680a(9) =10039825a(10) =88318136a(11) =819958033a(12) =8004898600a(13) =81913041721a(14) =876117919616