Numbers of the form 2^i - 2^j with i >= j.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =6a(6) =7a(7) =8a(8) =12a(9) =14a(10) =15a(11) =16a(12) =24a(13) =28a(14) =30a(15) =31a(16) =32a(17) =48a(18) =56a(19) =60a(20) =62a(21) =63a(22) =64a(23) =96a(24) =112a(25) =120a(26) =124a(27) =126a(28) =127a(29) =128