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A128031 Numbers k such that (17^k - 3^k)/14 is prime. 28
3, 11, 17, 491, 23029 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
All terms are primes.
No other terms < 100000.
LINKS
MATHEMATICA
k=14; Select[ Prime[ Range[1, 200] ], PrimeQ[ ((k+3)^# - 3^#)/k ]& ]
PROG
(PARI) is(n)=isprime((17^n-3^n)/14) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Cf. A028491 = numbers n such that (3^n - 1)/2 is prime.
Cf. A057468 = numbers n such that 3^n - 2^n is prime.
Cf. A059801 = numbers n such that 4^n - 3^n is prime.
Cf. A121877 = numbers n such that (5^n - 3^n)/2 is a prime.
Sequence in context: A124787 A080306 A128346 * A194128 A127995 A316839
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Feb 11 2007
EXTENSIONS
a(5)=23029 from Robert Price, Nov 03 2011
STATUS
approved

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Last modified April 14 03:22 EDT 2024. Contains 371652 sequences. (Running on oeis4.)