A217320 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A217320

Numbers n such that (13^n - 2^n)/11 is prime.

%I #11 Jun 06 2017 14:32:59

%S 3,5,31,73,89,521,3943,8719

%N Numbers n such that (13^n - 2^n)/11 is prime.

%C All terms are primes.

%C a(9) > 10^5.

%t Select[ Prime[ Range[1, 100000] ], PrimeQ[ (13^# - 2^#)/11 ]& ]

%o (PARI) is(n)=ispseudoprime((13^n-2^n)/11) \\ _Charles R Greathouse IV_, Jun 06 2017

%Y Cf. A128028, A016054, A210506.

%K hard,more,nonn

%O 1,1

%A _Robert Price_, Mar 18 2013