E.g.f.: exp(x + 2*x^2 + 3*x^3).

Terms

a(0) =1a(1) =1a(2) =5a(3) =31a(4) =145a(5) =1181a(6) =9661a(7) =77155a(8) =794081a(9) =8132185a(10) =86715541a(11) =1055208551a(12) =12921555505a(13) =166589628661