Binary expansion starts 11.

Terms

a(0) =3a(1) =6a(2) =7a(3) =12a(4) =13a(5) =14a(6) =15a(7) =24a(8) =25a(9) =26a(10) =27a(11) =28a(12) =29a(13) =30a(14) =31a(15) =48a(16) =49a(17) =50a(18) =51a(19) =52a(20) =53a(21) =54a(22) =55a(23) =56a(24) =57a(25) =58a(26) =59a(27) =60a(28) =61a(29) =62