Numbers k such that R_k + 7*10^k + 6 is prime, where R_k = 11...11 is the repunit (A002275) of length k.
A259138
Numbers k such that R_k + 7*10^k + 6 is prime, where R_k = 11...11 is the repunit (A002275) of length k.
Terms
- a(0) =0a(1) =10906a(2) =499210
External references
- oeis: A259138