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

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =0a(5) =-2a(6) =-5a(7) =-4a(8) =9a(9) =39a(10) =46a(11) =-101a(12) =-516a(13) =-624a(14) =2021a(15) =9704a(16) =8847a(17) =-58363a(18) =-230932a(19) =-65902a(20) =2085381a(21) =6301393a(22) =-5195375a(23) =-84748630a(24) =-174659303a(25) =535875052a(26) =3703162955a(27) =3578704451a(28) =-39485091237a(29) =-163826467050