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

Terms

a(0) =1a(1) =1a(2) =2a(3) =-1a(4) =-10a(5) =7a(6) =88a(7) =-68a(8) =-946a(9) =767a(10) =11298a(11) =-9425a(12) =-144024a(13) =122436a(14) =1919440a(15) =-1653776a(16) =-26419778a(17) =22992655a(18) =372670246a(19) =-326863667a(20) =-5358911450a(21) =4729547023a(22) =78264621664a(23) =-69424933968