G.f. satisfies A(x) = Sum_{n>=1} 2^(n-1) * A(x^(2*n))/A(x^n), with A(0) = 0 and A'(0) = 1.

Terms

a(0) =1a(1) =1a(2) =3a(3) =5a(4) =14a(5) =25a(6) =60a(7) =117a(8) =257a(9) =504a(10) =1053a(11) =2067a(12) =4197a(13) =8248a(14) =16491a(15) =32533a(16) =64919a(17) =128893a(18) =257923a(19) =515770a(20) =1036024a(21) =2080743a(22) =4185781a(23) =8411269a(24) =16893534a(25) =33867059a(26) =67793691a(27) =135460708a(28) =270330258a(29) =538950081