|
%I #12 Jun 11 2021 08:45:23
%S 5,7,17,23,43,71,239,733,1097
%N Numbers k such that (17^k - 5^k)/12 is prime.
%C All terms are primes.
%C a(10) > 10^5. - _Robert Price_, Jun 11 2013
%t k=17; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
%o (PARI) is(n)=isprime((17^n-5^n)/12) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128353, A128354.
%Y Cf. A004061, A082182, A121877, A059802.
%Y Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.
%K nonn,hard,more
%O 1,1
%A _Alexander Adamchuk_, Feb 27 2007
|
