Numbers k such that k prefixed by '9' and followed by '7' is prime.

Terms

a(0) =0a(1) =3a(2) =4a(3) =6a(4) =7a(5) =9a(6) =12a(7) =13a(8) =15a(9) =18a(10) =22a(11) =25a(12) =27a(13) =33a(14) =37a(15) =39a(16) =43a(17) =46a(18) =49a(19) =54a(20) =58a(21) =67a(22) =69a(23) =76a(24) =78a(25) =81a(26) =85a(27) =88a(28) =90a(29) =96