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Numbers k such that 357*2^k+1 is prime.
1

%I #15 May 30 2020 14:19:08

%S 2,3,7,8,10,14,18,23,26,27,35,44,46,50,55,56,59,67,80,115,138,248,280,

%T 319,372,416,454,624,662,686,702,707,806,847,866,1422,1930,2115,2835,

%U 3283,3358,3510,4420,9284,10007,10990,13775,14466,14558,16099,16319

%N Numbers k such that 357*2^k+1 is prime.

%H Jeppe Stig Nielsen, <a href="/A323003/b323003.txt">Table of n, a(n) for n = 1..79</a> (terms n = 1..77 from Robert Price)

%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>

%p select(k->isprime(357*2^k+1),[$1..1000]); # _Muniru A Asiru_, Jan 02 2019

%t Select[Range[1000], PrimeQ[357*2^# + 1] &] (* _Robert Price_, Jan 01 2019 *)

%K nonn,hard

%O 1,1

%A _Robert Price_, Jan 01 2019