Binary expansion starts 101.

Terms

a(0) =5a(1) =10a(2) =11a(3) =20a(4) =21a(5) =22a(6) =23a(7) =40a(8) =41a(9) =42a(10) =43a(11) =44a(12) =45a(13) =46a(14) =47a(15) =80a(16) =81a(17) =82a(18) =83a(19) =84a(20) =85a(21) =86a(22) =87a(23) =88a(24) =89a(25) =90a(26) =91a(27) =92a(28) =93a(29) =94