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Numbers k such that 149*2^k+1 is prime.
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%I #37 Apr 29 2019 17:11:55

%S 3,7,9,15,17,27,33,35,57,125,127,137,191,513,819,827,921,931,1047,

%T 1147,1599,1815,2499,2995,8151,11403,22783,29841,30201,85935,142281,

%U 149831,184457,221595,256099,283881,333933,483045,658917,714199,812719,1295061,1561951

%N Numbers k such that 149*2^k+1 is prime.

%C The subsequence of prime values starts 3, 7, 17, 127, 137, 191, 827, 22783, 714199, ... - _Muniru A Asiru_, Apr 29 2019

%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(149*2^k+1),[$0..1000])[]; # _Muniru A Asiru_, Dec 18 2018

%t Select[Range[1000], PrimeQ[149*2^# + 1] & ] (* _Robert Price_, Dec 18 2018 *)

%o (PARI) is(n)=ispseudoprime(149*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,more

%O 1,1

%A _James R. Buddenhagen_

%E Extended by _Hugo Pfoertner_, Jul 02 2003

%E a(33)-a(43) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 18 2018