a(n) = floor(n/2) mod floor(n/3).

Terms

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