G.f. satisfies A(x) = 1 + x*(1 + x*A(x)^5)^2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =11a(4) =50a(5) =275a(6) =1560a(7) =9212a(8) =56082a(9) =348675a(10) =2207120a(11) =14171155a(12) =92075064a(13) =604266000a(14) =3999688050a(15) =26670727220a(16) =178997024610