G.f. A(x) satisfies A(x) = 1 + x*(1 + x)^2*A(x)^3.

Terms

a(0) =1a(1) =1a(2) =5a(3) =25a(4) =145a(5) =905a(6) =5941a(7) =40433a(8) =282721a(9) =2018897a(10) =14661349a(11) =107945993a(12) =803922289a(13) =6045458905a(14) =45840518933a(15) =350100674785