E.g.f.: A(x) = exp( Sum_{n>=0} x^(2^n)/2^(2^n-1) ).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =13a(5) =41a(6) =166a(7) =652a(8) =3494a(9) =18118a(10) =114076a(11) =681176a(12) =5016892a(13) =35377564a(14) =288204008a(15) =2232198256a(16) =21124254181a(17) =191779964597