A032404 - OEIS

%I #27 Apr 04 2020 21:42:12

%S 6,14,58,62,318,1574,2034,26082,96838,103146,235106,1011102,1704658,

%T 2280194

%N Numbers k such that 109*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/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>

%o (PARI) is(n)=ispseudoprime(109*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,hard,more

%O 1,1

%A _James R. Buddenhagen_

%E a(11)-a(13) from http://www.prothsearch.com/riesel1.html by _Robert Price_, Dec 14 2018

%E a(14) from _Jeppe Stig Nielsen_, Apr 04 2020