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 A062215 #15 Aug 11 2024 14:41:34 %S A062215 3,33,133,1969,2335 %N A062215 Numbers k such that the smoothly undulating palindromic number (19*10^k - 91)/99 is a prime. %C A062215 Prime versus probable prime status and proofs are given in the author's table. %C A062215 No further terms < 100000. - _Ray Chandler_, Aug 17 2011 %H A062215 P. De Geest, <a href="https://www.worldofnumbers.com/undulat.htm#supp191">SUPP Reference Table - 191</a> %H A062215 <a href="/index/Pri#pri_supp">Index entries for sequences related to smoothly undulating palindromic primes</a> %e A062215 k=33 -> (19*10^33 - 91)/99 = 191919191919191919191919191919191. %Y A062215 Cf. A062209-A062232, A059758, A032758. %K A062215 nonn,base %O A062215 1,1 %A A062215 _Patrick De Geest_ and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001 %E A062215 Edited by _Ray Chandler_, Aug 17 2011