%I #8 May 30 2020 14:39:34
%S 5,7,17,41,175,14621,14711,25775,49591,120767,204809,655327,2007631
%N Numbers k such that 461*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[461*2^# + 1] &]
%K nonn,more,hard
%O 1,1
%A _Robert Price_, Jan 06 2019
%E a(13) from _Jeppe Stig Nielsen_, May 30 2020