Numbers k such that (151*10^k - 7)/9 is prime.

Terms

a(0) =1a(1) =4a(2) =6a(3) =12a(4) =13a(5) =15a(6) =18a(7) =30a(8) =49a(9) =72a(10) =799a(11) =832a(12) =877a(13) =1122a(14) =1968a(15) =2046a(16) =8176a(17) =11976a(18) =16444a(19) =20896a(20) =32941a(21) =67027a(22) =94885a(23) =154434