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%I #28 May 15 2023 02:17:20
%S 2,5,6,13,61,275,385,510,3559,9131,13075,13829,28530,29929
%N Numbers k such that 7^k - 5^k - 1 is prime.
%o (Magma) [n: n in [0..500]|IsPrime(7^n-5^n-1)];
%o (PARI) for(n=1,10000,if(isprime(7^n-5^n-1),print1(n,", "))); /* _Joerg Arndt_, May 15 2011 */
%K nonn,hard,more
%O 1,1
%A _Vincenzo Librandi_, Jan 22 2011
%E a(9)-a(12) from _Michael S. Branicky_, May 08 2021
%E a(13)-a(14) from _Michael S. Branicky_, May 14 2023
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