A181979 Numbers n such that (29^n - 1)/28 is prime.

5, 151, 3719, 49211, 77237

Offset: 1

Author

Robert Price, Apr 04 2012

Keywords

• hard
• more
• nonn

Links

• H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930.
• H. Lifchitz, Mersenne and Fermat primes field
• Index to primes in various ranges, form ((k+1)^n-1)/k

Programs

Mathematica

Select[Prime[Range[100000]], PrimeQ[(29^#-1)/28]&]

PARI

isok(n) = isprime((29^n-1)/28); \\ Michel Marcus, Mar 13 2016