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Numbers k such that 65^k - 64^k is prime.
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%I #25 Jul 04 2021 09:00:25

%S 5,31,9013,29077,35543,56809,60167

%N Numbers k such that 65^k - 64^k is prime.

%C Terms greater than 1000 are often only strong pseudoprimes.

%C All terms are prime. - _Robert Price_, Aug 09 2013

%C a(8) > 10^5. - _Robert Price_, Aug 09 2013

%o (PARI) is(n)=ispseudoprime(65^n-64^n) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. A000043, A057468, A059801, A059802, A062572-A062666.

%K nonn,hard,more

%O 1,1

%A _Mike Oakes_, May 18 2001, May 19 2001

%E a(4)-a(7) (calculations by Adam Marciniec) - _Robert Price_, Aug 09 2013