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 A009216 #18 Apr 01 2017 11:36:36
%S A009216 1,1,-1,-3,9,17,-145,21,2961,-9119,-58273,530541,177177,-24815503,
%T A009216 109736783,845196933,-11562650847,9274089409,818943535295,
%U A009216 -6145817165859,-30817061557719,818240768280017,-3016149953173201,-67401109608160779
%N A009216 E.g.f.: exp(sin(x)/exp(x)).
%t A009216 With[{nn=30}, CoefficientList[Series[Exp[Sin[x]/Exp[x]],{x,0,nn}],x] Range[ 0,nn]!] (* _Harvey P. Dale_, Feb 21 2013 *)
%K A009216 sign,easy
%O A009216 0,4
%A A009216 _R. H. Hardin_
%E A009216 Extended with signs by _Olivier Gérard_, Mar 15 1997
%E A009216 Definition clarified by _Harvey P. Dale_, Feb 21 2013