%I #6 Dec 31 2018 13:19:34
%S 7,11,243,291,327,1211,7331,26775,101603,171071,284795,295195,323871,
%T 589755,833467,1047471
%N Numbers k such that 317*2^k+1 is prime.
%H Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>
%H Ray Ballinger and Wilfrid Keller, <a href="http://www.prothsearch.com/riesel1a.html">List of primes k.2^n + 1 for 300 < k < 600</a>
%H Y. Gallot, <a href="http://www.utm.edu/research/primes/programs/gallot/index.html">Proth.exe: Windows Program for Finding Large Primes</a>
%H Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k.2^n - 1 for k < 300</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ProthPrime.html">Proth Prime</a>
%H <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>
%t Select[Range[1000], PrimeQ[317*2^# + 1] &] (* _Robert Price_, Dec 31 2018 *)
%Y Cf. A002255,A050527.
%K nonn,more,hard
%O 1,1
%A _Robert Price_, Dec 31 2018
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