G.f. satisfies: A(x) = Sum_{n>=0} x^(n^2) * A(x)^(n^2+n).

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =15a(5) =50a(6) =177a(7) =649a(8) =2437a(9) =9322a(10) =36214a(11) =142546a(12) =567409a(13) =2280246a(14) =9238883a(15) =37699021a(16) =154783906a(17) =638983998a(18) =2650697658a(19) =11043733080a(20) =46192300706a(21) =193892210528a(22) =816486626337