E.g.f. satisfies A(x) = exp(x*A(-x^4)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =-119a(6) =-719a(7) =-2519a(8) =-6719a(9) =166321a(10) =3598561a(11) =29882161a(12) =159572161a(13) =-389343239a(14) =-55939643759a(15) =-974399385959