G.f. A(x) satisfies: A(x) = Sum_{n>=0} [x*A(x)]^(2^n-1).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =11a(6) =24a(7) =58a(8) =149a(9) =385a(10) =1001a(11) =2652a(12) =7140a(13) =19384a(14) =52944a(15) =145590a(16) =402949a(17) =1121117a(18) =3133255a(19) =8793372a(20) =24774557a(21) =70045871a(22) =198672464a(23) =565144064a(24) =1611946284a(25) =4609140916a(26) =13209415116a(27) =37937455636a(28) =109171460104a(29) =314736939884