Numbers k such that (397*10^k + 53)/9 is prime.

Terms

a(0) =5a(1) =9a(2) =17a(3) =47a(4) =54a(5) =75a(6) =191a(7) =207a(8) =267a(9) =894a(10) =2099a(11) =7164a(12) =8625a(13) =10865a(14) =20394a(15) =22251a(16) =23088a(17) =29015a(18) =92369