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 A007313 M3149 #20 Jan 27 2014 08:54:42 %S A007313 1,-1,-3,-41,-1035,-40721,-2291331,-174783865,-17394878523, %T A007313 -2192620580129,-341767803858867,-64587124941406473, %U A007313 -14555427555355014123,-3857289820949315456817 %N A007313 Reversion of g.f. for Euler (secant) numbers A000364. %D A007313 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A007313 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %H A007313 <a href="/index/Res#revert">Index entries for reversions of series</a> %Y A007313 Cf. A000364. %K A007313 sign %O A007313 1,3 %A A007313 _N. J. A. Sloane_, _Mira Bernstein_ %E A007313 Extended with signs by _Christian G. Bower_, Oct 15 1999