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 A296439 #12 Mar 27 2019 10:04:17
%S A296439 0,1,1,4,0,53,-155,2364,-15288,216817,-2147215,32932700,-433435816,
%T A296439 7431919285,-120703007451,2326504612964,-44614898438480,
%U A296439 963118686971137,-21195404220321151,508991484878443860,-12604990423335824688,334199905021923072597,-9181752759370241656699,266806716890671639953964
%N A296439 Expansion of e.g.f. log(1 + arctanh(x))*exp(x).
%H A296439 Andrew Howroyd, <a href="/A296439/b296439.txt">Table of n, a(n) for n = 0..200</a>
%F A296439 E.g.f.: log(1 + (log(1 + x) - log(1 - x))/2)*exp(x).
%F A296439 a(n) ~ -(-1)^n * (n-1)! * exp((1-exp(2))/(1+exp(2))) * ((exp(2)+1)/(exp(2)-1))^n. - _Vaclav Kotesovec_, Dec 21 2017
%e A296439 E.g.f.: A(x) = x/1! + x^2/2! + 4*x^3/3! + 53*x^5/5! - 155*x^6/6! + 2364*x^7/7! - 15288*x^8/8! + ...
%p A296439 a:=series(log(1+arctanh(x))*exp(x),x=0,24): seq(n!*coeff(a,x,n),n=0..23); # _Paolo P. Lava_, Mar 27 2019
%t A296439 nmax = 23; CoefficientList[Series[Log[1 + ArcTanh[x]] Exp[x], {x, 0, nmax}], x] Range[0, nmax]!
%t A296439 nmax = 23; CoefficientList[Series[Log[1 + (Log[1 + x] - Log[1 - x])/2] Exp[x], {x, 0, nmax}], x] Range[0, nmax]!
%o A296439 (PARI) my(ox=O(x^30)); Vecrev(Pol(serlaplace(log(1 + atanh(x + ox)) * exp(x + ox)))) \\ _Andrew Howroyd_, Dec 12 2017
%Y A296439 Cf. A009371, A009390, A009393, A202139, A291484, A296438.
%K A296439 sign
%O A296439 0,4
%A A296439 _Ilya Gutkovskiy_, Dec 12 2017