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%I #33 Jun 07 2021 04:50:38
%S 2,3,4,29,31,34,53,65,94,202,288,415,457,483,703,762,1285,1464,2094,
%T 3384,9335,15955,18910,73119,125418,143273,584279
%N Numbers k such that 6^k - 5 is prime.
%C The next term in the sequence is greater than 12400. - _Dmitry Kamenetsky_, Oct 02 2008
%H Henri Lifchitz and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=5%5En%2B2&action=Search">PRP Records</a>.
%e 65 is present because 6^65 - 5 is prime.
%o (PARI) is(n)=ispseudoprime(6^n-5) \\ _Charles R Greathouse IV_, Feb 20 2017
%K nonn
%O 1,1
%A _Andrey V. Kulsha_, Feb 09 2001
%E a(21), corresponding to a probable prime, from _Dmitry Kamenetsky_, Oct 02 2008
%E a(22)-a(23) from _Henri Lifchitz_
%E a(24)-a(25) from Lelio R. Paula
%E a(26) from _Paul Bourdelais_, Jan 28 2021
%E a(27) from _Paul Bourdelais_, Feb 26 2021