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

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =12a(6) =30a(7) =80a(8) =219a(9) =609a(10) =1724a(11) =4953a(12) =14388a(13) =42193a(14) =124768a(15) =371602a(16) =1113667a(17) =3356017a(18) =10162979a(19) =30911457a(20) =94390590a(21) =289258448a(22) =889304859a(23) =2742205395a(24) =8478653638a(25) =26280715255a(26) =81648362339a(27) =254204771596a(28) =793011895972