Primes of the form 20*R_k + 3, where R_k is the repunit (A002275) of length k.
A093162
Primes of the form 20*R_k + 3, where R_k is the repunit (A002275) of length k.
Terms
- a(0) =3a(1) =23a(2) =223a(3) =22222223a(4) =22222222223
External references
- oeis: A093162