Partial sums of Mertens's function (A002321).

Terms

a(0) =1a(1) =1a(2) =0a(3) =-1a(4) =-3a(5) =-4a(6) =-6a(7) =-8a(8) =-10a(9) =-11a(10) =-13a(11) =-15a(12) =-18a(13) =-20a(14) =-21a(15) =-22a(16) =-24a(17) =-26a(18) =-29a(19) =-32a(20) =-34a(21) =-35a(22) =-37a(23) =-39a(24) =-41a(25) =-42a(26) =-43a(27) =-44a(28) =-46a(29) =-49