A225955 Numbers n such that (15^n - 2^n)/13 is prime.

2, 5, 11, 167, 317, 337, 349, 3449, 7517, 23003

Offset: 1

Author

Robert Price, May 21 2013

Keywords

• more
• nonn

Comments

All terms are primes.

a(11) > 2*10^5.

Crossrefs

Cf. A128028, A016054, A217320, A006033.

Programs

Mathematica

Select[ Prime[ Range[1, 100000] ], PrimeQ[ (15^# - 2^#)/13 ]& ]

PARI

is(n)=ispseudoprime((15^n-2^n)/13) \\ Charles R Greathouse IV, May 22 2017