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

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =-4a(5) =-14a(6) =-30a(7) =12a(8) =330a(9) =1139a(10) =2226a(11) =-2288a(12) =-39646a(13) =-163742a(14) =-410900a(15) =-89273a(16) =5352720a(17) =31177720a(18) =114624554a(19) =234094417a(20) =-312845870a(21) =-5584935715a(22) =-32878240028a(23) =-127407695297a(24) =-315375599410a(25) =24759230680