a(n) = Sum_{i=0..n-1} K(i,n)*i, where K(,) is Kronecker symbol.

Terms

a(0) =0a(1) =1a(2) =-1a(3) =4a(4) =0a(5) =6a(6) =-7a(7) =0a(8) =27a(9) =6a(10) =-11a(11) =-8a(12) =0a(13) =20a(14) =-30a(15) =64a(16) =0a(17) =-4a(18) =-19a(19) =0a(20) =0a(21) =46a(22) =-69a(23) =-48a(24) =250a(25) =106a(26) =-9a(27) =0a(28) =0a(29) =68