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A225955
Numbers n such that (15^n - 2^n)/13 is prime.
3
2, 5, 11, 167, 317, 337, 349, 3449, 7517, 23003
OFFSET
1,1
COMMENTS
All terms are primes.
a(11) > 2*10^5.
MATHEMATICA
Select[ Prime[ Range[1, 100000] ], PrimeQ[ (15^# - 2^#)/13 ]& ]
PROG
(PARI) is(n)=ispseudoprime((15^n-2^n)/13) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Robert Price, May 21 2013
STATUS
approved