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Numbers n such that 51*2^n-1 is prime.
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%I #18 Jan 17 2019 10:08:17

%S 1,9,10,19,22,57,69,97,141,169,171,195,238,735,885,1287,1365,2026,

%T 2211,2361,2889,3159,3709,5031,19066,33622,43162,188517,194875,217971,

%U 286965,331546,468417,657705,832630

%N Numbers n such that 51*2^n-1 is prime.

%C 845494 is also in the sequence. - Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008

%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(51*2^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K hard,nonn

%O 1,2

%A _N. J. A. Sloane_, Dec 29 1999

%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008