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

Terms

a(0) =1a(1) =-1a(2) =-3a(3) =6a(4) =1a(5) =-20a(6) =24a(7) =38a(8) =-132a(9) =34a(10) =411a(11) =-632a(12) =-601a(13) =2914a(14) =-1664a(15) =-7822a(16) =15649a(17) =6802a(18) =-62082a(19) =55672a(20) =141109a(21) =-369310a(22) =-12036a(23) =1275642a(24) =-1580834a(25) =-2343886a(26) =8375349a(27) =-2648282a(28) =-25217490a(29) =41097852