Numbers k such that 78*10^k - 7 is prime.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =11a(5) =14a(6) =15a(7) =16a(8) =18a(9) =21a(10) =28a(11) =44a(12) =55a(13) =286a(14) =304a(15) =494a(16) =970a(17) =1611a(18) =2051a(19) =2756a(20) =6452a(21) =16758a(22) =29291a(23) =98413a(24) =113954a(25) =197702