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%I #24 Jan 17 2019 10:08:17
%S 4,16,48,60,240,256,304,2644,3720,25132,39472,212460,592968
%N Numbers k such that 149*2^k-1 is prime.
%C All terms appear to be multiples of four. - _Robert Price_, Dec 23 2018
%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>.
%t Select[Range[1000], PrimeQ[149*2^# - 1] & ] (* _Robert Price_, Dec 23 2018 *)
%o (PARI) is(n)=ispseudoprime(149*2^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K hard,nonn,more
%O 1,1
%A _N. J. A. Sloane_, Dec 29 1999
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008