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A227046
Numbers n such that (17^n + 5^n)/22 is prime.
7
3, 29, 151, 2153, 5717, 9133, 9973, 79537
OFFSET
1,1
COMMENTS
All terms are primes.
a(9) > 10^5.
MATHEMATICA
k=17; Do[p=Prime[n]; f=(k^p+5^p)/(k+5); If[ PrimeQ[f], Print[p] ], {n, 1, 9592}]
PROG
(PARI) is(n)=ispseudoprime((17^n+5^n)/22) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Robert Price, Jun 29 2013
STATUS
approved