

A128336


Numbers n such that (6^n + 5^n)/11 is prime.


26




OFFSET

1,1


COMMENTS

All terms are primes.
No other terms less than 100000.  Robert Price, May 11 2012.


LINKS

Table of n, a(n) for n=1..10.


MATHEMATICA

k=6; Do[p=Prime[n]; f=(k^p+5^p)/(k+5); If[ PrimeQ[f], Print[p] ], {n, 1, 100}]


PROG

(PARI) forprime(p=3, 1e4, if(ispseudoprime((6^p+5^p)/11), print1(p", "))) \\ Charles R Greathouse IV, Jul 16 2011


CROSSREFS

Cf. A057171, A082387, A122853, A128335, A128337, A128338, A128339, A128340, A128341, A128342, A128343, A004061, A082182, A121877, A059802, A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128353, A128354.
Sequence in context: A123599 A100270 A016045 * A278735 A094487 A007516
Adjacent sequences: A128333 A128334 A128335 * A128337 A128338 A128339


KEYWORD

hard,more,nonn


AUTHOR

Alexander Adamchuk, Feb 27 2007


EXTENSIONS

a(7)a(9) from Alexander Adamchuk, May 04 2010
One more term (8783) added (unknown discoverer) corresponding to a probable prime with 6834 digits by JeanLouis Charton, Oct 06 2010


STATUS

approved



