G.f. satisfies A(x) = A(x^2) + A(x^2)^2*A(x^3)/A(x^6), with A(0) = 0 and A'(0) = 1.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =5a(5) =4a(6) =9a(7) =7a(8) =20a(9) =14a(10) =31a(11) =24a(12) =60a(13) =40a(14) =90a(15) =66a(16) =167a(17) =108a(18) =241a(19) =176a(20) =414a(21) =263a(22) =586a(23) =418a(24) =987a(25) =615a(26) =1352a(27) =966a(28) =2185a(29) =1350