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A128348 Numbers n such that (12^n - 5^n)/7 is prime. 18
2, 3, 31, 41, 53, 101, 421 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

All terms are primes.

MATHEMATICA

k=12; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n, 1, 100}]

CROSSREFS

Cf. A062572, A128344, A128345, A128346, A128347, A128349, A128350, A128351, A128352, A128353, A128354. Cf. A004061, A082182, A121877, A059802. Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Sequence in context: A136150 A155056 A110456 * A029973 A054551 A049065

Adjacent sequences:  A128345 A128346 A128347 * A128349 A128350 A128351

KEYWORD

hard,more,nonn

AUTHOR

Alexander Adamchuk (alex(AT)kolmogorov.com), Feb 27 2007

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Last modified February 15 12:05 EST 2012. Contains 205782 sequences.