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%I #22 Jan 17 2019 10:08:17
%S 3,5,7,9,11,17,23,31,35,43,47,83,85,99,101,195,267,281,363,391,519,
%T 623,653,673,701,1091,1147,1565,3273,3661,3923,4127,4783,5267,5345,
%U 5747,6151,6299,7569,9033,11843,14139,14175,15779,21557,32295,49823,60979,65195,132367,133895,186827,212647
%N Numbers k such that 181*2^k-1 is prime.
%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 Kosmaj, <a href="http://www.15k.org/riesellist.html">Riesel list 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[181*2^# - 1] & ] (* _Robert Price_, Dec 29 2018 *)
%o (PARI) is(n)=ispseudoprime(181*2^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K hard,nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 29 1999
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
%E a(49)-a(53) from the Wilfrid Keller link by _Robert Price_, Dec 29 2018
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