Numbers k such that 25*10^(2*k) + 5*10^k + 1 are prime.
A308449
Numbers k such that 25*10^(2*k) + 5*10^k + 1 are prime.
Terms
- a(0) =0a(1) =1a(2) =2a(3) =14a(4) =174a(5) =448a(6) =16562
External references
- oeis: A308449
A308449
Numbers k such that 25*10^(2*k) + 5*10^k + 1 are prime.