A229542 - OEIS

%I #15 Jun 05 2021 16:45:15

%S 11,19,79,631,1787,2011,2381,20219,49523

%N Numbers n such that (19^n - 2^n)/17 is prime.

%C All terms are primes.

%C a(10) > 2*10^5.

%t Select[ Prime[ Range[1, 100000] ], PrimeQ[ (19^# - 2^#)/17 ]& ]

%o (PARI) is(n)=ispseudoprime((19^n-2^n)/17) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. A128032, A225955, A225807, A006035.

%K nonn,hard,more

%O 1,1

%A _Robert Price_, Sep 25 2013