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 A075838 #35 Apr 29 2023 06:57:22
%S A075838 9,5,2,8,4,7,8,6,4,6,5,4,9,4,1,9,4,7,4,4,1,3,3,3,2,1,8,5,8,0,4,8,3,3,
%T A075838 5,1,7,4,7,5,2,1,5,6,0,8,0,6,4,0,1,6,0,6,0,9,6,7,8,2,2,7,9,9,9,7,2,7,
%U A075838 2,1,2,0,4,9,7,8,9,7,5,1,1,3,7,8,5,8,0,8,3,1,7,3,2,3,1,5
%N A075838 Decimal expansion of the solution to the donkey problem.
%H A075838 Dr. Math, <a href="https://web.archive.org/web/20200801034958/http://mathforum.org:80/dr.math/faq/faq.grazing.html">Grazing Animals</a>.
%H A075838 Marshall Fraser, <a href="http://www.jstor.org/stable/2690163">A tale of two goats</a>, Math. Mag., 55 (1982), 221-227. [_N. J. A. Sloane_, Jul 12 2011]
%F A075838 x: 4x*cos^2(x) + (1/2)Pi - 2x - sin(2x) = 0.
%e A075838 0.95284786465494194744133321858048335174752156080640...
%t A075838 RealDigits[x /. FindRoot[4*x*Cos[x]^2 + Pi/2 - 2*x - Sin[2*x] == 0, {x, 1}, WorkingPrecision -> 120], 10, 105][[1]] (* _Amiram Eldar_, Apr 29 2023 *)
%o A075838 (PARI) solve(x=0, 1, 4*x*cos(x)^2 + Pi/2 - 2*x - sin(2*x)) \\ _Michel Marcus_, Sep 19 2017
%Y A075838 Cf. A133731, A173571, A192930.
%K A075838 easy,nonn,cons
%O A075838 0,1
%A A075838 _Zak Seidov_, Oct 17 2002