Numbers k such that (7*10^k - 439)/9 is prime.

Terms

a(0) =2a(1) =20a(2) =34a(3) =35a(4) =65a(5) =73a(6) =89a(7) =94a(8) =103a(9) =157a(10) =208a(11) =217a(12) =430a(13) =508a(14) =1220a(15) =4729a(16) =5218a(17) =6350a(18) =11810a(19) =29893a(20) =37753a(21) =89539a(22) =165350