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

Terms

a(0) =1a(1) =3a(2) =13a(3) =63a(4) =345a(5) =2043a(6) =13029a(7) =88119a(8) =629169a(9) =4707315a(10) =36772029a(11) =298608687a(12) =2513795337a(13) =21874602987a(14) =196341166485