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 A093535 #6 Jan 09 2009 03:00:00 %S A093535 3,7,31,127,3583,8191,131071,524287,14680063,1073479679,2147483647 %N A093535 Duplicate of A081093. %K A093535 dead %O A093535 1,1