(# 1's)-(# 0's) in first n terms of A030308.

Terms

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