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 A002811 M3927 N1615 #15 Jun 01 2017 23:26:51 %S A002811 1,5,23,1681,257543,67637281,27138236663,15442193173681 %N A002811 Erroneous version of A002439. %D A002811 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002811 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %K A002811 dead %O A002811 1,2