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 A002258 M1165 N0445 #51 Dec 21 2024 09:46:10 %S A002258 1,2,4,9,10,12,27,37,38,44,48,78,112,168,229,297,339,517,522,654,900, %T A002258 1518,2808,2875,3128,3888,4410,6804,7050,7392,19219,21445,21550,24105, %U A002258 24995,34224,34260,43388,48444,61758,184290,294894,300488,403929,483098,635989 %N A002258 Numbers k such that 15*2^k + 1 is prime. %D A002258 H. Riesel, "Prime numbers and computer methods for factorization," Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384. %D A002258 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002258 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002258 Jeppe Stig Nielsen, <a href="/A002258/b002258.txt">Table of n, a(n) for n = 1..63</a> %H A002258 Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a> %H A002258 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 A002258 Y. Gallot, <a href="http://www.utm.edu/research/primes/programs/gallot/index.html">Proth.exe: Windows Program for Finding Large Primes</a> %H A002258 Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k.2^n - 1 for k < 300</a> %H A002258 R. M. Robinson, <a href="https://doi.org/10.1090/S0002-9939-1958-0096614-7">A report on primes of the form k.2^n+1 and on factors of Fermat numbers</a>, Proc. Amer. Math. Soc., 9 (1958), 673-681. %H A002258 <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 A002258 Select[Range[1000], PrimeQ[15*2^#+1] &] (* _Amiram Eldar_, Dec 12 2018 *) %o A002258 (PARI) for(n=1, 10^10, if(ispseudoprime(15<<n+1), print1(n,", "))); \\ _Joerg Arndt_, Feb 23 2014 %K A002258 hard,nonn %O A002258 1,2 %A A002258 _N. J. A. Sloane_ %E A002258 Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), _Joerg Arndt_, Apr 07 2013 %E A002258 a(57)-a(60) from http://www.prothsearch.com/riesel1.html by _Robert Price_, Dec 12 2018 %E A002258 Terms moved from Data to b-file, and one new term put in b-file, by _Jeppe Stig Nielsen_, Oct 16 2019