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

Terms

a(0) =1a(1) =-1a(2) =3a(3) =-5a(4) =4a(5) =-2a(6) =9a(7) =-23a(8) =22a(9) =-8a(10) =12a(11) =-24a(12) =27a(13) =-67a(14) =128a(15) =-112a(16) =38a(17) =-2a(18) =50a(19) =-154a(20) =183a(21) =-219a(22) =464a(23) =-600a(24) =404a(25) =-272a(26) =262a(27) =-146a(28) =100a(29) =-408