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 A260337 #3 Jul 29 2015 13:46:03 %S A260337 1,2,5,17,73,388,2461,18156 %N A260337 Erroneous version of A002135. %H A260337 T. Muir, <a href="/A002135/a002135_1.pdf">The Theory of Determinants in the Historical Order of Development</a>, 4 vols., Macmillan, NY, 1906-1923. [Annotated scans of selected pages]. See Vol. 3, p. 112. %K A260337 dead %O A260337 1,2