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

Terms

a(0) =1a(1) =1a(2) =2a(3) =7a(4) =27a(5) =112a(6) =492a(7) =2243a(8) =10513a(9) =50353a(10) =245353a(11) =1212398a(12) =6061225a(13) =30601910a(14) =155808915a(15) =799096655a(16) =4124491215a(17) =21408066097a(18) =111672838857a(19) =585128521777