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Numbers k such that 147*2^k+1 is prime.
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%I #32 Jan 19 2020 13:30:19

%S 8,11,15,18,19,26,44,60,84,90,91,134,155,179,258,275,475,620,824,888,

%T 1731,2194,2328,2568,2915,3554,4319,5340,8054,10088,21660,41851,50535,

%U 77719,81660,169658,179034,190911,208731,218300,359710,394394,509831,534558

%N Numbers k such that 147*2^k+1 is prime.

%H Jeppe Stig Nielsen, <a href="/A032423/b032423.txt">Table of n, a(n) for n = 1..52</a>

%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>

%p select(k->isprime(147*2^k+1),[$0..1000])[]; # _Muniru A Asiru_, Dec 18 2018

%t Select[Range[1000], PrimeQ[147*2^# + 1] & ] (* _Robert Price_, Dec 18 2018 *)

%o (PARI) is(n)=ispseudoprime(147*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn

%O 1,1

%A _James R. Buddenhagen_

%E a(36)-a(49) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 18 2018

%E Terms moved from Data section to b-file, and more terms appended to b-file, by _Jeppe Stig Nielsen_, Jan 19 2020