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 A198133 #6 Feb 07 2025 16:44:04
%S A198133 5,9,3,7,8,0,8,1,2,6,7,9,1,5,9,0,3,7,6,6,0,8,1,6,4,5,5,6,1,0,9,9,4,7,
%T A198133 8,4,6,8,2,5,0,7,3,4,4,8,9,8,0,6,8,7,9,9,6,6,1,0,5,7,3,4,5,7,0,3,4,7,
%U A198133 3,5,1,7,4,8,9,9,2,7,6,1,0,6,0,3,6,9,0,2,9,3,1,1,7,3,8,6,8,5,7
%N A198133 Decimal expansion of greatest x having 2*x^2+3x=3*cos(x).
%C A198133 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198133 least x: -1.53498632262030720596966252020141464...
%e A198133 greatest x: 0.593780812679159037660816455610994...
%t A198133 a = 2; b = 3; c = 3;
%t A198133 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198133 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A198133 r1 = x /. FindRoot[f[x] == g[x], {x, -1.54, -1.53}, WorkingPrecision -> 110]
%t A198133 RealDigits[r1](* A198132 *)
%t A198133 r2 = x /. FindRoot[f[x] == g[x], {x, .59, .60}, WorkingPrecision -> 110]
%t A198133 RealDigits[r2](* A198133 *)
%Y A198133 Cf. A197737.
%K A198133 nonn,cons
%O A198133 0,1
%A A198133 _Clark Kimberling_, Oct 22 2011