Numbers k such that (68*10^k - 257)/9 is prime.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =11a(5) =20a(6) =22a(7) =32a(8) =40a(9) =62a(10) =95a(11) =104a(12) =569a(13) =710a(14) =955a(15) =1682a(16) =2933a(17) =4592a(18) =10286a(19) =16634a(20) =19235a(21) =20437a(22) =31024a(23) =48304a(24) =79813a(25) =128645a(26) =148060