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%I #13 Jul 04 2021 07:53:17
%S 2,1097,2243,2857,4357,6803,20747,24571
%N Numbers k such that (15^k - 4^k)/11 is prime.
%C All terms are prime.
%C a(9) > 10^5.
%C a(1) is trivially prime, the remainder are probable primes.
%t Select[Prime[Range[1, 100000]], PrimeQ[(15^# - 4^#)/11]&]
%o (PARI) is(n)=ispseudoprime((15^n-4^n)/11) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A004063, A028491, A057468, A059801, A121877, A128024, A128025, A128026, A128027, A128028, A128029, A128030, A128031, A128032, A210506, A128347, A225955, A062581.
%K nonn,hard,more
%O 1,1
%A _Robert Price_, May 01 2014
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