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 A124005 #21 Oct 08 2019 19:54:50 %S A124005 1,4,12,54,236,1288,7092,42614,269352,1743560,11922442,80209268, %T A124005 562280115,3772081046 %N A124005 Number of different Othello positions at the end of the n-th ply. %H A124005 Alain Brobecker, <a href="http://abrobecker.free.fr/text/othello.pdf">Othello and retrograde analysis (pdf)</a> %H A124005 Alain Brobecker, <a href="http://abrobecker.free.fr/tools/othello.zip">programs to generate sequences</a> %H A124005 Alain Brobecker, <a href="http://abrobecker.free.fr/tools/othello.c">othello.c</a> %Y A124005 Cf. A124004, A124006. %K A124005 fini,hard,nonn %O A124005 0,2 %A A124005 Alain Brobecker (abrobecker(AT)yahoo.com), Nov 01 2006, Dec 30 2006 %E A124005 Edited by _Charles R Greathouse IV_, Oct 28 2009 %E A124005 a(10) from _Dominic Hofer_, Mar 28 2018 %E A124005 a(11)-a(13) from _Dominic Hofer_, Sep 28 2019