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 A287591 #30 Apr 21 2024 09:59:44 %S A287591 656601,25536531021,8829751133841,60561233400921,79934093254401, %T A287591 352609909731201,598438077923841,976515437206401,2122162714918401, %U A287591 2789066007968241,3767175573114801,7881891474971361,10740122274670881,11512252145095521,16924806963384321 %N A287591 Carmichael numbers k such that k-2 and k+2 are both primes. %C A287591 Rotkiewicz conjectured that there are infinitely many Carmichael numbers k such that k-2 or k+2 are primes. %C A287591 The terms were calculated using Pinch's tables of Carmichael numbers (see link below). %H A287591 Amiram Eldar, <a href="/A287591/b287591.txt">Table of n, a(n) for n = 1..282</a> (terms below 10^22, calculated using data from Claude Goutier) %H A287591 Claude Goutier, <a href="http://www-labs.iro.umontreal.ca/~goutier/OEIS/A055553/">Compressed text file carm10e22.gz containing all the Carmichael numbers up to 10^22</a>. %H A287591 R. G. E. Pinch, <a href="http://www.s369624816.websitehome.co.uk/rgep/cartable.html">Tables relating to Carmichael numbers</a>. %H A287591 Andrzej Rotkiewicz, <a href="http://dml.cz/dmlcz/137472">On pseudoprimes having special forms and a solution of K. Szymiczek's problem</a>, Acta Mathematica Universitatis Ostraviensis, Vol. 13, No. 1 (2005), pp. 57-71. %e A287591 656601 is in the sequence since it is a Carmichael number (A002997) and both 656599 and 656603 are primes. %Y A287591 Cf. A002997, A057942, A272754. %Y A287591 Subsequence of A258801. %K A287591 nonn %O A287591 1,1 %A A287591 _Amiram Eldar_, May 26 2017