G.f. satisfies: A(x) = exp( Sum_{n>=1} A(x^n) / A(-x^n) * x^n/n ).

Terms

a(0) =1a(1) =1a(2) =3a(3) =5a(4) =14a(5) =28a(6) =77a(7) =173a(8) =485a(9) =1165a(10) =3335a(11) =8341a(12) =24331a(13) =62455a(14) =184783a(15) =483127a(16) =1445429a(17) =3830911a(18) =11562247a(19) =30969809a(20) =94134108a(21) =254285698a(22) =777410651a(23) =2114690863a(24) =6496549393a(25) =17774924057a(26) =54831676621a(27) =150766702399a(28) =466729836290