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Numbers k such that 92^k - 91^k is prime.
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%I #18 Jul 04 2021 09:02:47

%S 3,827,9439,27701,36683

%N Numbers k such that 92^k - 91^k is prime.

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

%C a(6) > 10^5. - _Robert Price_, Aug 05 2015

%t Select[Range[0, 10000], If[PrimeQ[#], PrimeQ[92^# - 91^#]] &] (* _Robert Price_, Aug 05 2015 *)

%o (PARI) is_ok(n)=isprime(92^n-91^n);

%o first(m)=my(v=vector(m),k=3);v[1]=3;for(i=2,m,while(!is_ok(k),k++);print1(k,", ");v[i]=k;k++;);v; /* _Anders Hellström_, Aug 05 2015 */

%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)-a(5) from _Robert Price_, Aug 05 2015 (Computer run by Adam Marciniec)