G.f. satisfies A(x) = exp( Sum_{k>=1} (-1)^(k+1) * (2^k + A(x^k)) * x^k/k ).

Terms

a(0) =1a(1) =3a(2) =5a(3) =14a(4) =38a(5) =114a(6) =360a(7) =1166a(8) =3872a(9) =13094a(10) =44961a(11) =156244a(12) =548636a(13) =1943333a(14) =6935817a(15) =24917586a(16) =90039163a(17) =327029681a(18) =1193258619a(19) =4371901789a(20) =16077606949a(21) =59325057056a(22) =219579151797a(23) =815017718383