G.f. A(x) satisfies: A(x+x^2) = A(x)^2/(1+x).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =6a(5) =27a(6) =160a(7) =1189a(8) =10600a(9) =110161a(10) =1306629a(11) =17408293a(12) =257299241a(13) =4177017722a(14) =73872560359