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%I #17 Jul 04 2021 09:00:31
%S 17,23,421,1303,6163,17117,18439,74521
%N Numbers k such that 62^k - 61^k is prime.
%C Terms greater than 1000 are often only strong pseudoprimes.
%C All terms are primes. - _Robert Price_, May 07 2013
%C a(9) > 10^5. - _Robert Price_, May 07 2013
%o (PARI) is(n)=ispseudoprime(62^n-61^n) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A000043, A057468, A059801, A059802, A062572-A062666.
%K nonn,hard
%O 1,1
%A _Mike Oakes_, May 18 2001, May 19 2001
%E a(6)-a(8) (Computer runs by Adam Marciniec) from _Robert Price_, May 07 2013