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Numbers k such that 369*2^k+1 is prime.
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%I #11 Dec 20 2024 08:08:48

%S 1,3,13,39,61,99,111,121,142,385,1753,2203,2581,3603,8674,10507,13815,

%T 19231,49255,53593,56754,73849,98655,100710,171001,241359,423535,

%U 617047,623979,1209435,1240510,2093022,2846547,3365614,3805321

%N Numbers k such that 369*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/riesel1a.html">List of primes k.2^n + 1 for 300 < k < 600</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 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ProthPrime.html">Proth Prime</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[369*2^# + 1] &] (* _Robert Price_, Jan 01 2019 *)

%K nonn,more,hard

%O 1,2

%A _Robert Price_, Jan 01 2019

%E a(32)-a(33) from _Jeppe Stig Nielsen_, Feb 16 2020

%E a(34)-a(35) from _Jeppe Stig Nielsen_, Dec 20 2024