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 A198119 #6 Feb 07 2025 16:44:04
%S A198119 8,9,5,6,5,2,3,8,1,3,5,8,4,2,8,9,0,1,2,1,8,1,7,6,4,7,2,1,3,5,3,7,1,4,
%T A198119 7,5,8,5,7,2,8,2,6,9,1,0,7,0,9,1,2,9,4,1,6,6,7,0,7,1,1,4,7,3,5,4,5,1,
%U A198119 6,6,9,0,9,7,0,1,9,2,6,0,7,5,9,3,8,2,1,7,1,4,6,6,9,5,4,8,4,2,9
%N A198119 Decimal expansion of greatest x having 2*x^2+x=4*cos(x).
%C A198119 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198119 least x: -1.1690226923053929102101002288527830...
%e A198119 greatest x: 0.89565238135842890121817647213537147...
%t A198119 a = 2; b = 1; c = 4;
%t A198119 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198119 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A198119 r1 = x /. FindRoot[f[x] == g[x], {x, -1.17, -1.16}, WorkingPrecision -> 110]
%t A198119 RealDigits[r1](* A198118 *)
%t A198119 r2 = x /. FindRoot[f[x] == g[x], {x, .8, .9}, WorkingPrecision -> 110]
%t A198119 RealDigits[r2](* A198119 *)
%Y A198119 Cf. A197737.
%K A198119 nonn,cons
%O A198119 0,1
%A A198119 _Clark Kimberling_, Oct 21 2011