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A128350 Numbers k such that (14^k - 5^k)/9 is prime. 18
2, 151, 673, 709, 2999, 17909, 77213 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
All terms are primes.
a(8) > 10^5. - Robert Price, Apr 23 2013
LINKS
MATHEMATICA
k=14; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n, 1, 200}]
PROG
(PARI) is(n)=isprime((14^n-5^n)/9) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Sequence in context: A141130 A157074 A329712 * A046473 A261967 A024245
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Feb 27 2007
EXTENSIONS
One more term from Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008
a(6) and a(7) from Robert Price, Apr 23 2013
STATUS
approved

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Last modified April 15 14:56 EDT 2024. Contains 371691 sequences. (Running on oeis4.)