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 A013192 #9 Feb 06 2019 12:26:08
%S A013192 0,1,0,1,-4,33,-168,1377,-9504,99649,-930560,11796673,-137207552,
%T A013192 2017677153,-28086102016,471591223841,-7659623550976,144742585812609,
%U A013192 -2686461109796864,56447611418620289
%N A013192 Expansion of e.g.f. log(cosh(x) + arctanh(x)).
%e A013192 x + 1/3!*x^3 - 4/4!*x^4 + 33/5!*x^5 - 168/6!*x^6 ...
%t A013192 With[{nn=20},CoefficientList[Series[Log[Cosh[x]+ArcTanh[x]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Feb 06 2019 *)
%K A013192 sign
%O A013192 0,5
%A A013192 Patrick Demichel (patrick.demichel(AT)hp.com)
%E A013192 a(0)=0 inserted and title improved by _Sean A. Irvine_, Aug 01 2018