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%I #20 Jan 17 2019 10:08:17
%S 1,5,7,9,13,15,29,33,39,55,81,95,205,279,581,807,813,2551,2565,3183,
%T 6661,11989,16911,22605,30799,39969,41167,43421,54559,212745,290631,
%U 332231,460989,542945,691469
%N Numbers n such that 49*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(49*2^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A032374, 49*2^n+1 is prime.
%K hard,nonn
%O 1,2
%A _N. J. A. Sloane_, Dec 29 1999
%E More terms from _Hugo Pfoertner_, Oct 13 2004
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
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