Smallest nonempty set S containing prime divisors of 2k + 1 for each k in S.
A020575
Smallest nonempty set S containing prime divisors of 2k + 1 for each k in S.
Terms
- a(0) =3a(1) =5a(2) =7a(3) =11a(4) =13a(5) =19a(6) =23a(7) =47
External references
- oeis: A020575