Numbers whose base-4 representation has one fewer 0 than 3's.

Terms

a(0) =3a(1) =7a(2) =11a(3) =13a(4) =14a(5) =23a(6) =27a(7) =29a(8) =30a(9) =39a(10) =43a(11) =45a(12) =46a(13) =51a(14) =53a(15) =54a(16) =57a(17) =58a(18) =60a(19) =79a(20) =87a(21) =91a(22) =93a(23) =94a(24) =103a(25) =107a(26) =109a(27) =110a(28) =115a(29) =117