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 A198116 #6 Feb 07 2025 16:44:04
%S A198116 1,1,0,6,6,9,5,8,9,2,8,6,3,5,0,3,1,2,3,6,0,5,9,4,5,6,7,5,9,2,0,8,2,0,
%T A198116 8,0,2,3,1,2,9,0,8,0,2,1,7,5,4,9,9,6,7,8,5,5,3,0,1,5,2,5,0,9,8,6,6,6,
%U A198116 8,0,9,5,3,5,3,2,9,3,1,6,5,5,2,8,1,8,1,9,3,3,2,0,6,8,3,5,1,4,0
%N A198116 Decimal expansion of least x having 2*x^2+x=3*cos(x).
%C A198116 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198116 least x: -1.1066958928635031236059456759208208...
%e A198116 greatest x: 0.80159198729974720435776444320005779...
%t A198116 a = 2; b = 1; c = 3;
%t A198116 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198116 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A198116 r1 = x /. FindRoot[f[x] == g[x], {x, -1.2, -1.1}, WorkingPrecision -> 110]
%t A198116 RealDigits[r1] (* A198116 *)
%t A198116 r2 = x /. FindRoot[f[x] == g[x], {x, .8, .9}, WorkingPrecision -> 110]
%t A198116 RealDigits[r2](* A198117 *)
%Y A198116 Cf. A197737.
%K A198116 nonn,cons
%O A198116 1,4
%A A198116 _Clark Kimberling_, Oct 21 2011