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 A023383 #17 Apr 19 2014 07:48:01 %S A023383 5,10,20,40,130,1010,13020,404040,100412130,201201142010, %T A023383 11244024443021020,43242234044024403133040, %U A023383 141203414122301104243434200224130 %N A023383 a(n+1) = a(n) converted to base 10 from base 5 (written in base 10). %H A023383 Vincenzo Librandi, <a href="/A023383/b023383.txt">Table of n, a(n) for n = 1..22</a> %t A023383 NestList[FromDigits[IntegerDigits[#,5]]&,5,15] (* _Harvey P. Dale_, Jul 22 2012 *) %Y A023383 Cf. A023390. %K A023383 nonn,base %O A023383 1,1 %A A023383 _David W. Wilson_