Numbers k such that (14*10^k - 221)/9 is prime.

Terms

a(0) =2a(1) =3a(2) =15a(3) =17a(4) =21a(5) =38a(6) =93a(7) =323a(8) =410a(9) =413a(10) =444a(11) =884a(12) =1836a(13) =2192a(14) =3527a(15) =4700a(16) =6260a(17) =6944a(18) =8229a(19) =10320a(20) =27480a(21) =31425a(22) =32937a(23) =108545a(24) =155024a(25) =182177a(26) =196965