G.f.: Sum_{n>=0} x^n * (x^(n+1) + i)^n / (1 + i*x^(n+1))^(n+1).

Terms

a(0) =1a(1) =0a(2) =-2a(3) =3a(4) =2a(5) =0a(6) =-2a(7) =-14a(8) =15a(9) =0a(10) =-2a(11) =22a(12) =2a(13) =0a(14) =-84a(15) =33a(16) =2a(17) =0a(18) =-2a(19) =38a(20) =172a(21) =0a(22) =-2a(23) =-508a(24) =323a(25) =0a(26) =-292a(27) =54a(28) =2a(29) =0