G.f. A(x) satisfies: A(x - x/(1+x)*A(x)) = x.

Terms

a(0) =1a(1) =1a(2) =2a(3) =7a(4) =31a(5) =159a(6) =909a(7) =5657a(8) =37750a(9) =267367a(10) =1995167a(11) =15601743a(12) =127317160a(13) =1080705251a(14) =9517003663a(15) =86763537749a(16) =817415449402