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%I #18 Jan 17 2019 10:08:17
%S 2,5,9,11,17,21,29,30,33,50,59,62,137,161,281,290,533,842,1410,1553,
%T 4794,5529,5661,7013,7470,19605,63477,72513,152942,201494,220562,
%U 236117,291705,313433,372342,386430,389225,531347,565917,810347,832410
%N Numbers n such that 291*2^n-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 <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>
%H Kosmaj, <a href="http://www.15k.org/riesellist.html">Riesel list k<300</a>.
%o (PARI) is(n)=ispseudoprime(291*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