This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A322958 #10 Feb 16 2025 08:33:57 %S A322958 4,8,12,20,28,36,120,184,200,756,788,1304,6412,7848,12944,40116,45056, %T A322958 67520,129172,204592,225568,615116,803668,1646668,2917844 %N A322958 Numbers k such that 331*2^k+1 is prime. %H A322958 Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a> %H A322958 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 A322958 Y. Gallot, <a href="http://www.utm.edu/research/primes/programs/gallot/index.html">Proth.exe: Windows Program for Finding Large Primes</a> %H A322958 Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k.2^n - 1 for k < 300</a> %H A322958 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ProthPrime.html">Proth Prime</a> %H A322958 <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 A322958 select(n->isprime(331*2^n+1),[$1..1000]); # _Muniru A Asiru_, Dec 31 2018 %t A322958 Select[Range[1000], PrimeQ[331*2^# + 1] &] (* _Robert Price_, Dec 31 2018 *) %Y A322958 Cf. A002255, A050527. %K A322958 nonn,more,hard %O A322958 1,1 %A A322958 _Robert Price_, Dec 31 2018 %E A322958 a(25) from _Jeppe Stig Nielsen_, Dec 20 2024