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Numbers n such that 265*2^n-1 is prime.
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%I #18 Jan 17 2019 10:08:17

%S 11,17,19,21,37,49,59,145,163,289,587,737,1029,1061,1873,2265,3271,

%T 3943,5429,6067,6133,6277,10101,10967,11497,18799,27551,34883,37459,

%U 44897,74743,113473,323083

%N Numbers n such that 265*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(265*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