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%I #21 Jun 07 2021 01:10:45
%S 0,1,2,4,5,10,11,16,20,52,75,106,112,132,371,3264,3424,5477,7516,
%T 10365,44557,150706
%N Numbers k such that 15^k + 2 is prime.
%C No further terms < 100000. - _Ray Chandler_, Aug 05 2011
%C a(23) > 2*10^5. - _Robert Price_, Jun 23 2015
%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=15%5En%2B2&action=Search">PRP Records</a>.
%t Do[ f = 15^n + 2; If[ PrimeQ[ f ], Print[ {n, f} ] ], {n, 1, 371} ]
%o (PARI) is(n)=ispseudoprime(15^n+2) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A051783 (k such that 3^k + 2 is prime).
%Y Cf. A087885 (k such that 5^k + 2 is prime).
%Y Cf. A090649, A109076, A113480, A138049, A138050, A138051, A087886, A113481.
%K nonn,more
%O 1,3
%A _Alexander Adamchuk_, Mar 02 2008
%E a(16)-a(19) from _Ray Chandler_, Jul 30 2011
%E a(20) found by Lelio R Paula, Dec 2006
%E a(21) from _Ray Chandler_, Jul 31 2011
%E a(22) from _Robert Price_, Jun 23 2015
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