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Numbers k such that 45*2^k+1 is prime.
1

%I #36 Dec 28 2019 14:39:12

%S 2,9,12,14,23,24,29,60,189,200,333,372,443,464,801,1374,6146,6284,

%T 6359,6923,12293,16679,18660,19301,29240,32018,38457,48612,56754,

%U 67394,76416,79160,91403,97116,110303,129731,159318,202304,243321,426653,458712,574506

%N Numbers k such that 45*2^k+1 is prime.

%H Jeppe Stig Nielsen, <a href="/A032372/b032372.txt">Table of n, a(n) for n = 1..55</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 Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</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>

%o (PARI) is(n)=ispseudoprime(45*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn

%O 1,1

%A _James R. Buddenhagen_

%E More terms from _Hugo Pfoertner_, Jun 20 2003

%E More terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), _Joerg Arndt_, Apr 07 2013

%E a(40) and beyond from _Jeppe Stig Nielsen_, Sep 19 2019