%I #14 Jul 04 2021 09:01:42

%S 7,277,6133

%N Numbers k such that 80^k - 79^k is prime.

%C Terms > 1000 are often only strong pseudoprimes.

%C a(4) > 10^5. - _Robert Price_, Dec 12 2014

%o (PARI) is(n)=ispseudoprime(80^n-79^n) \\ _Charles R Greathouse IV_, Jun 13 2017

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

%K nonn,hard,bref

%O 1,1

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