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A128351 Numbers n such that (16^n - 5^n)/11 is prime. 18
7, 13, 109, 139, 967, 60013, 97613 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are primes.

a(8) > 10^5 - Robert Price, Jul 03 2013

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

k=16; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n, 1, 100}]

PROG

(PARI) is(n)=isprime((16^n-5^n)/11) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128352, A128353, A128354, A004061, A082182, A121877, A059802, A057171, A082387, A122853, A128335-A128342.

Sequence in context: A035030 A046519 A283920 * A192894 A241280 A219703

Adjacent sequences:  A128348 A128349 A128350 * A128352 A128353 A128354

KEYWORD

hard,more,nonn

AUTHOR

Alexander Adamchuk, Feb 27 2007

EXTENSIONS

a(6)-a(7) from Robert Price, Jul 03 2013

STATUS

approved

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Last modified June 15 22:19 EDT 2019. Contains 324145 sequences. (Running on oeis4.)