Numbers k such that k prefixed by '1' and followed by '3' is prime.

Terms

a(0) =0a(1) =1a(2) =6a(3) =7a(4) =9a(5) =10a(6) =12a(7) =15a(8) =16a(9) =19a(10) =21a(11) =22a(12) =28a(13) =30a(14) =37a(15) =42a(16) =43a(17) =45a(18) =48a(19) =49a(20) =52a(21) =54a(22) =55a(23) =58a(24) =61a(25) =66a(26) =69a(27) =72a(28) =73a(29) =75