Semiprimes having only holey digits (0,4,6,8,9).

Terms

a(0) =4a(1) =6a(2) =9a(3) =46a(4) =49a(5) =69a(6) =86a(7) =94a(8) =446a(9) =466a(10) =469a(11) =489a(12) =649a(13) =669a(14) =689a(15) =694a(16) =698a(17) =699a(18) =849a(19) =866a(20) =869a(21) =886a(22) =889a(23) =898a(24) =899a(25) =949a(26) =989a(27) =998a(28) =4006a(29) =4009