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 A013890 #19 Sep 08 2022 08:44:38 %S A013890 19,47045881,116490258898219,288441413567621167681, %T A013890 714209495693373205673756419,1768453418076865701195582595329481, %U A013890 4378865740046709085864680868712732574619,10842505080063916320800450434338728415281531281,26847115986241183138017674520015691090350184323352819 %N A013890 a(n) = 19^(5*n + 1). %H A013890 Vincenzo Librandi, <a href="/A013890/b013890.txt">Table of n, a(n) for n = 0..50</a> %H A013890 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a> %H A013890 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (2476099). %F A013890 a(n) = 2476099*a(n-1), a(0)=19. - _Vincenzo Librandi_, May 27 2011 %t A013890 NestList[2476099#&,19,20] (* _Harvey P. Dale_, Dec 23 2016 *) %o A013890 (Magma) [19^(5*n+1): n in [0..10]]; // _Vincenzo Librandi_, May 27 2011 %Y A013890 Cf. A001029. %K A013890 nonn %O A013890 0,1 %A A013890 _N. J. A. Sloane_