Numbers k such that 5*10^k + 3*R_k + 6 is prime, where R_k = 11...1 is the repunit (A002275) of length k.
A103012
Numbers k such that 5*10^k + 3*R_k + 6 is prime, where R_k = 11...1 is the repunit (A002275) of length k.
Terms
- a(0) =0a(1) =1a(2) =47a(3) =69a(4) =99a(5) =575a(6) =715a(7) =2179a(8) =10541
External references
- oeis: A103012