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Numbers k such that 151*2^k+1 is prime.
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%I #28 Mar 12 2020 20:54:35

%S 4,20,24,76,96,544,560,1124,1760,5056,6104,9680,31416,84640,281244,

%T 301056,585044,809716,858640,1016600,1376256,2584480

%N Numbers k such that 151*2^k+1 is prime.

%H Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>

%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 Y. Gallot, <a href="http://www.utm.edu/research/primes/programs/gallot/index.html">Proth.exe: Windows Program for Finding Large Primes</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>

%t Select[Range[1000], PrimeQ[151*2^# + 1] & ] (* _Robert Price_, Dec 18 2018 *)

%o (PARI) is(n)=ispseudoprime(151*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,more

%O 1,1

%A _James R. Buddenhagen_

%E a(15)-a(21) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 18 2018

%E a(22) from _Jeppe Stig Nielsen_, Mar 12 2020