Numbers n for which R(n) - 10^floor(n/2) is prime, where R(n) = (10^n-1)/9.
A331862
Numbers n for which R(n) - 10^floor(n/2) is prime, where R(n) = (10^n-1)/9.
Terms
- a(0) =3a(1) =26a(2) =186a(3) =206a(4) =258a(5) =3486a(6) =12602
External references
- oeis: A331862