Numerators of Farey (or Stern-Brocot) tree fractions.

Terms

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