A032388 - OEIS

%I #30 Dec 22 2024 20:03:21

%S 3,7,19,23,95,287,483,559,655,667,1639,9399,39639,63883,71575,164319,

%T 401947,614995,2762047,5422903

%N Numbers k such that 77*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(77*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,changed

%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(19)-a(20) from _Jeppe Stig Nielsen_, Dec 22 2024