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A128032 Numbers k such that (19^k - 3^k)/16 is prime. 28
73, 271, 421, 2711 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
All terms are primes.
No other terms <= 10^5. - Robert Price, Aug 27 2011
LINKS
MATHEMATICA
k=16; Select[ Prime[ Range[1, 200] ], PrimeQ[ ((k+3)^# - 3^#)/k ]& ]
PROG
(PARI) is(n)=isprime((19^n-3^n)/16) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Sequence in context: A071392 A305473 A142434 * A142489 A033244 A140857
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Feb 11 2007
EXTENSIONS
2711 from Farideh Firoozbakht, Apr 07 2007
STATUS
approved

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Last modified April 23 13:04 EDT 2024. Contains 371913 sequences. (Running on oeis4.)