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%I A002269 M0640 N0234 #52 Aug 30 2020 02:30:16
%S A002269 1,2,3,5,7,10,11,13,14,18,21,22,31,42,67,70,71,73,251,370,375,389,407,
%T A002269 518,818,865,1057,1602,2211,3049,4802,4865,5317,7583,8061,9853,10217,
%U A002269 12103,13721,14927,15441,15931,16709,18907,20221,21882,25654,28437,30325
%N A002269 Numbers k such that 39*2^k + 1 is prime.
%D A002269 H. Riesel, "Prime numbers and computer methods for factorization," Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384.
%D A002269 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A002269 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A002269 Jeppe Stig Nielsen, <a href="/A002269/b002269.txt">Table of n, a(n) for n = 1..84</a>
%H A002269 Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>
%H A002269 Ray Ballinger and Wilfrid Keller, <a href="http://www.prothsearch.com/riesel1.html">List of primes k.2^n + 1 for k < 300</a>
%H A002269 Y. Gallot, <a href="http://www.utm.edu/research/primes/programs/gallot/index.html">Proth.exe: Windows Program for Finding Large Primes</a>
%H A002269 Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k.2^n - 1 for k < 300</a>
%H A002269 R. M. Robinson, <a href="https://doi.org/10.1090/S0002-9939-1958-0096614-7">A report on primes of the form k.2^n+1 and on factors of Fermat numbers</a>, Proc. Amer. Math. Soc., 9 (1958), 673-681.
%H A002269 <a href="/index/Pri#riesel">Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime</a>
%o A002269 (PARI) is(n)=ispseudoprime(39*2^n+1) \\ _Charles R Greathouse IV_, Jun 06 2017
%K A002269 hard,nonn
%O A002269 1,2
%A A002269 _N. J. A. Sloane_
%E A002269 Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), _Joerg Arndt_, Apr 07 2013
%E A002269 a(77) from http://www.prothsearch.com/riesel1.html by _Robert Price_, Dec 14 2018
%E A002269 Terms moved from Data section to b-file, and new terms put in b-file, by _Jeppe Stig Nielsen_, Sep 29 2019

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