A225955 - OEIS

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A225955

Numbers n such that (15^n - 2^n)/13 is prime.

%I #14 May 22 2021 16:11:53

%S 2,5,11,167,317,337,349,3449,7517,23003

%N Numbers n such that (15^n - 2^n)/13 is prime.

%C All terms are primes.

%C a(11) > 2*10^5.

%t Select[ Prime[ Range[1, 100000] ], PrimeQ[ (15^# - 2^#)/13 ]& ]

%o (PARI) is(n)=ispseudoprime((15^n-2^n)/13) \\ _Charles R Greathouse IV_, May 22 2017

%Y Cf. A128028, A016054, A217320, A006033.

%K more,nonn

%O 1,1

%A _Robert Price_, May 21 2013