a(n)=(# 1's)-(# 2's) in first n terms of A030567.

Terms

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