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%I #25 Apr 04 2020 19:21:19
%S 8,10,22,44,58,62,68,82,100,104,118,230,260,440,446,512,700,892,932,
%T 1240,1456,2438,4982,5090,6496,14678,17944,23786,27838,39866,46322,
%U 52358,61700,68584,78244,180410,397096,404962,693656,803446,871438,1065400,1356316
%N Numbers k such that 223*2^k+1 is prime.
%H Jeppe Stig Nielsen, <a href="/A032488/b032488.txt">Table of n, a(n) for n = 1..46</a>
%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/riesel1.html">List of primes k.2^n + 1 for k < 300</a>
%H Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k.2^n - 1 for k < 300</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[223*2^# + 1] & ] (* _Robert Price_, Dec 19 2018 *)
%o (PARI) is(n)=ispseudoprime(223*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn,hard
%O 1,1
%A _N. J. A. Sloane_.
%E a(36)-a(43) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 19 2018
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