G.f.: Sum_{k>=0} x^(k^2)*(-1)^k/(Product_{i=1..k} 1-x^i).

Terms

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