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 A024248 #9 Apr 02 2017 15:23:01 %S A024248 0,1,4,-12,-2272,-166960,-13136448,-1177426880,-116571720704, %T A024248 -11452654888704,-669616618900480,214088681811547136, %U A024248 155062926684742508544,76744341986122463531008,36379718195920790292840448 %N A024248 Expansion of sin(tan(x)*x)/2. %t A024248 Sin[ Tan[ x ]*x ]/2 (* Even Part *) %Y A024248 Cf. A009515. %K A024248 sign %O A024248 0,3 %A A024248 _R. H. Hardin_ %E A024248 Extended with signs Mar 1997