G.f. A(x) satisfies: A(x) = Product_{k>=1} (1 + x^k*A(x))^k.

Terms

a(0) =1a(1) =1a(2) =3a(3) =10a(4) =31a(5) =102a(6) =342a(7) =1167a(8) =4046a(9) =14213a(10) =50464a(11) =180847a(12) =653296a(13) =2376406a(14) =8697194a(15) =32002219a(16) =118322499a(17) =439364380a(18) =1637827543a(19) =6126870808a(20) =22993190147a(21) =86542625565a(22) =326607659370