Numbers k such that (19*10^k + 521)/9 is prime.

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =34a(5) =218a(6) =253a(7) =310a(8) =362a(9) =370a(10) =568a(11) =574a(12) =607a(13) =919a(14) =1615a(15) =3968a(16) =5950a(17) =10435a(18) =11887a(19) =176932