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 A062223 #16 Oct 31 2019 01:23:41 %S A062223 5,17,2069,6815,20417,25745 %N A062223 Numbers k such that the smoothly undulating palindromic number (74*10^k - 47)/99 is a prime. %C A062223 Prime versus probable prime status and proofs are given in the author's table. %C A062223 No further terms < 100000. - _Ray Chandler_, Aug 17 2011 %H A062223 Patrick De Geest, <a href="http://www.worldofnumbers.com/undulat.htm#supp747">SUPP Reference Table - 747</a> %H A062223 <a href="/index/Pri#pri_supp">Index entries for sequences related to smoothly undulating palindromic primes</a> %e A062223 k=17 -> (74*10^17 - 47)/99 = 74747474747474747. %Y A062223 Cf. A062209-A062232, A059758, A032758. %K A062223 nonn,base,more %O A062223 1,1 %A A062223 _Patrick De Geest_ and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001 %E A062223 Edited by _Ray Chandler_, Aug 17 2011