Numbers k such that k prefixed by '5' and followed by '3' is prime.

Terms

a(0) =0a(1) =2a(2) =6a(3) =9a(4) =11a(5) =15a(6) =23a(7) =27a(8) =30a(9) =32a(10) =33a(11) =39a(12) =41a(13) =44a(14) =48a(15) =50a(16) =56a(17) =57a(18) =62a(19) =65a(20) =68a(21) =69a(22) =74a(23) =78a(24) =81a(25) =84a(26) =90a(27) =92a(28) =95a(29) =104