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Kosmaj, <a href="http://www.15k.org/riesellist.htmhtml">Riesel list k<300</a>.
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Numbers n k such that 273*2^nk-1 is prime.
2, 6, 10, 15, 22, 26, 31, 42, 47, 98, 107, 123, 126, 175, 178, 203, 223, 230, 239, 279, 371, 402, 519, 607, 755, 830, 871, 927, 980, 1527, 1770, 2007, 2218, 2247, 2250, 3982, 4367, 4510, 9716, 13018, 20906, 26340, 40186, 63332, 84599, 119743, 156155, 206118, 238687
<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>
<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>
Select[Range[1000], PrimeQ[273*2^# - 1] & ] (* Robert Price, Dec 30 2018 *)
a(48)-a(49) from the Wilfrid Keller link by Robert Price, Dec 30 2018
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Ray Ballinger and Wilfrid Keller, <a href="http://www.prothsearch.com/rieselriesel1.html">List of primes k.2^n + 1 for k < 300</a>
Ray Ballinger and Wilfrid Keller, <a href="http://web.archive.org/web/20161028080239/http://wwwnetcom/riesel.html">List of primes k.2^n + 1 for k < 300</a>
Wilfrid Keller, <a href="http://web.archive.org/web/20161028021640/http://wwwnetcom/riesel2.html">List of primes k.2^n - 1 for k < 300</a>
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(PARI) is(n)=ispseudoprime(273*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
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Ray Ballinger and Wilfrid Keller, <a href="http://web.archive.org/web/20161028080239/http://www