G.f. A(x) satisfies A(x) = 1 + x*A(-x)^4.

Terms

a(0) =1a(1) =1a(2) =-4a(3) =-10a(4) =84a(5) =265a(6) =-2604a(7) =-8900a(8) =94692a(9) =337940a(10) =-3767312a(11) =-13812674a(12) =158785964a(13) =593029550a(14) =-6967201736a(15) =-26372738120a(16) =314904180100