%I #31 Dec 21 2024 03:42:59
%S 2,4,8,10,12,14,20,22,24,32,56,76,84,86,92,118,164,382,604,1148,1900,
%T 2440,2554,2798,3160,6092,7142,14044,14782,21056,24852,29084,44252,
%U 46022,101318,294216,412366,493738,769740,923728,1206136,1596836,2023486,3801284
%N Numbers k such that 235*2^k+1 is prime.
%H Jeppe Stig Nielsen, <a href="/A032494/b032494.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[235*2^# + 1] & ] (* _Robert Price_, Dec 19 2018 *)
%o (PARI) is(n)=ispseudoprime(235*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(42) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 19 2018
%E a(43) from _Jeppe Stig Nielsen_, May 31 2020
%E a(44) from _Jeppe Stig Nielsen_, Dec 21 2024