Composite numbers whose prime factors contain no digits other than 3 and 4.

Terms

a(0) =9a(1) =27a(2) =81a(3) =129a(4) =243a(5) =387a(6) =729a(7) =1161a(8) =1299a(9) =1329a(10) =1849a(11) =2187a(12) =3483a(13) =3897a(14) =3987a(15) =5547a(16) =6561a(17) =10029a(18) =10299a(19) =10449a(20) =11691a(21) =11961a(22) =16641a(23) =18619a(24) =19049a(25) =19683a(26) =30087a(27) =30897a(28) =31347a(29) =35073