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

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =10a(5) =42a(6) =194a(7) =979a(8) =5274a(9) =30037a(10) =179527a(11) =1120612a(12) =7280750a(13) =49120810a(14) =343547469a(15) =2487670468a(16) =18631824735a(17) =144215785791