Composite numbers whose prime factors contain no digits other than 2 and 9.

Terms

a(0) =4a(1) =8a(2) =16a(3) =32a(4) =58a(5) =64a(6) =116a(7) =128a(8) =232a(9) =256a(10) =458a(11) =464a(12) =512a(13) =841a(14) =916a(15) =928a(16) =1024a(17) =1682a(18) =1832a(19) =1856a(20) =1858a(21) =2048a(22) =3364a(23) =3664a(24) =3712a(25) =3716a(26) =4096a(27) =5998a(28) =6641a(29) =6728