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 A200288 #12 Feb 12 2025 14:34:01
%S A200288 7,1,9,3,8,4,2,6,0,4,5,9,8,7,5,8,3,2,1,0,7,5,5,2,4,1,1,5,9,1,3,8,0,6,
%T A200288 1,7,5,5,7,6,3,3,7,2,7,5,5,4,2,4,6,3,4,1,9,6,7,5,8,9,1,7,2,4,8,5,5,8,
%U A200288 5,3,7,4,4,4,3,4,0,5,7,4,5,9,8,7,5,5,2,9,0,4,2,5,1,9,8,0,5,8,3
%N A200288 Decimal expansion of greatest x satisfying 4*x^2 - cos(x) = 2*sin(x).
%C A200288 See A199949 for a guide to related sequences. The Mathematica program includes a graph.
%H A200288 G. C. Greubel, <a href="/A200288/b200288.txt">Table of n, a(n) for n = 0..10000</a>
%H A200288 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A200288 least x: -0.300931885421902370031006240717514956...
%e A200288 greatest x: 0.7193842604598758321075524115913806...
%t A200288 a = 4; b = -1; c = 2;
%t A200288 f[x_] := a*x^2 + b*Cos[x]; g[x_] := c*Sin[x]
%t A200288 Plot[{f[x], g[x]}, {x, -1, 1}, {AxesOrigin -> {0, 0}}]
%t A200288 r = x /. FindRoot[f[x] == g[x], {x, -.31, -.30}, WorkingPrecision -> 110]
%t A200288 RealDigits[r] (* A200287 *)
%t A200288 r = x /. FindRoot[f[x] == g[x], {x, .71, .72}, WorkingPrecision -> 110]
%t A200288 RealDigits[r] (* A200288 *)
%o A200288 (PARI) a=4; b=-1; c=2; solve(x=0, 1, a*x^2 + b*cos(x) - c*sin(x)) \\ _G. C. Greubel_, Jul 07 2018
%Y A200288 Cf. A199949.
%K A200288 nonn,cons
%O A200288 0,1
%A A200288 _Clark Kimberling_, Nov 15 2011