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 A239138 #12 Jun 09 2016 10:40:26 %S A239138 1,2,3,4,5,6,7,8,9,99,999,9999,99999,999999,9999999,99999999, %T A239138 999999999,9999999999,99999999999,999999999999,9999999999999, %U A239138 99999999999999,999999999999999,9999999999999999,99999999999999999,999999999999999999,9999999999999999999 %N A239138 The sequence S = a(1), a(2), ... is defined by a(1)=1, if d,e,f are consecutive digits then we do not have d <= e > f, and S is always extended with the smallest integer not yet present in S. %C A239138 Computed by Lars Blomberg. %D A239138 Eric Angelini, Posting to Sequence Fans Mailing List, Sep 28 2013 %H A239138 Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/LittleEqualGreat.htm">Less than <, Equal to =, Greater than ></a> (see sequence Sh) %H A239138 Eric Angelini, <a href="/A239083/a239083.pdf">Less than <, Equal to =, Greater than ></a> [Cached copy, with permission of the author] %Y A239138 The sequences in this family are given in A239083-A239086, A239136-A239139, A239087-A239090, A239215-A239218, A239235. %K A239138 nonn,base %O A239138 1,2 %A A239138 _Michel Marcus_, Mar 11 2014