%I #20 Jul 04 2021 07:53:50
%S 5,1427,2357,24499
%N Numbers k such that 32^k - 31^k is prime.
%C Terms > 1000 often correspond only to strong pseudoprimes.
%C a(5) > 10^5. - _Robert Price_, Oct 03 2012
%o (PARI) is(n)=ispseudoprime(32^n-31^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(4) from _Robert Price_, Oct 03 2012
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