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 A110708 #24 Jan 20 2025 20:50:10
%S A110708 0,1,-1,0,2,8,-64,-112,2064,8192,-157056,-599808,16072704,80010240,
%T A110708 -2484268032,-13537247232,506459129856,3160676007936,-135526008225792,
%U A110708 -929451393220608,45507663438741504,343173318976733184,-18834884514478817280,-154043745649772986368
%N A110708 E.g.f. log(1+arctan(x)).
%H A110708 G. C. Greubel, <a href="/A110708/b110708.txt">Table of n, a(n) for n = 0..450</a>
%F A110708 a(n) = n!*Sum_{m=0..(n-1)/2} (2^(2*m-n)*(n-2*m)!*(-1)^(n-m-1) * (Sum_{i=0..2*m} (2^(i+n-2*m)*Stirling1(n-2*m+i,n-2*m)*binomial(n-1,n-2*m+i-1))/(n-2*m+i)!))/(n-2*m).
%t A110708 With[{nn = 50}, CoefficientList[Series[Log[1 + ArcTan[x]], {x, 0, nn}], x]*Range[0, nn]!] (* _G. C. Greubel_, Sep 06 2017 *)
%o A110708 (Maxima)
%o A110708 a(n):=2*n!*sum((2^(-(n-2*m)-1)*(n-2*m)!*(-1)^(n-m-1)*sum((2^(i+n-2*m)*stirling1(n-2*m+i,n-2*m)*binomial(n-1,n-2*m+i-1))/(n-2*m+i)!,i,0,2*m))/(n-2*m),m,0,(n-1)/2);
%o A110708 (Maxima) b[1]:1$ b[n]:=sum((-1)^(k+1)*b[n-1-2*k]/(2*k+1),k,0,floor(n/2)-1)+((%i)^(n-1)+(-%i)^(n-1))/2;
%o A110708 cons(0,makelist((n-1)!*b[n],n,1,100)); /* _Tani Akinari_, Oct 30 2017 */
%o A110708 (PARI) my(x='x+O('x^50)); concat([0], Vec(serlaplace(log(1 + atan(x))))) \\ _G. C. Greubel_, Sep 06 2017
%K A110708 sign
%O A110708 0,5
%A A110708 _Vladimir Kruchinin_, Jun 12 2011