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

Terms

a(0) =0a(1) =1a(2) =3a(3) =6a(4) =10a(5) =12a(6) =15a(7) =21a(8) =22a(9) =30a(10) =34a(11) =36a(12) =45a(13) =48a(14) =49a(15) =52a(16) =54a(17) =55a(18) =58a(19) =63a(20) =64a(21) =66a(22) =69a(23) =75a(24) =78a(25) =82a(26) =87a(27) =91a(28) =94a(29) =103