G.f.: A(x) = exp( Sum_{n>=1} (Sum_{k=0..2*n} A027907(n,k)^2 * x^k / A(x)^k) * x^n/n ).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =11a(6) =19a(7) =34a(8) =61a(9) =106a(10) =181a(11) =311a(12) =543a(13) =955a(14) =1668a(15) =2885a(16) =4980a(17) =8650a(18) =15114a(19) =26391a(20) =45845a(21) =79385a(22) =137718a(23) =239866a(24) =418338a(25) =727926a(26) =1263097a(27) =2191463a(28) =3810775a(29) =6638258