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 A024338 #15 Apr 02 2017 15:42:04
%S A024338 0,0,1,-3,15,-80,542,-4158,37228,-374592,4237120,-53017712,729890528,
%T A024338 -10957004864,178355968576,-3129133077376,58889303575296,
%U A024338 -1183497066823680,25300855990394880,-573326855846475776
%N A024338 Expansion of log(1+x)*log(1+tan(x))/2.
%t A024338 With[{nn=20},CoefficientList[Series[Log[1+x]Log[1+Tan[x]]/2,{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Oct 27 2011 *)
%Y A024338 Cf. A009422.
%K A024338 sign
%O A024338 0,4
%A A024338 _R. H. Hardin_
%E A024338 Extended with signs, Mar 1997