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 A198364 #8 Feb 07 2025 16:44:05
%S A198364 4,0,0,3,0,3,9,9,5,2,5,5,1,8,5,9,1,4,6,3,0,6,3,7,1,8,6,8,3,4,2,0,3,5,
%T A198364 7,2,4,6,4,1,5,2,9,6,5,1,0,7,0,7,9,4,9,2,4,4,3,2,3,2,8,6,3,4,2,8,9,9,
%U A198364 3,8,5,5,3,3,2,2,1,0,4,0,7,9,7,2,4,9,5,1,8,7,4,3,8,5,2,2,6,0,3
%N A198364 Decimal expansion of greatest x having 4*x^2+3x=2*cos(x).
%C A198364 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198364 least x: -1.0119640719541596551643922516868104...
%e A198364 greatest x: 0.4003039952551859146306371868342035...
%t A198364 a = 4; b = 3; c = 2;
%t A198364 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198364 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A198364 r1 = x /. FindRoot[f[x] == g[x], {x, -1.1, -1.0}, WorkingPrecision -> 110]
%t A198364 RealDigits[r1] (* A198363 *)
%t A198364 r2 = x /. FindRoot[f[x] == g[x], {x, .4, .41}, WorkingPrecision -> 110]
%t A198364 RealDigits[r2] (* A198364 *)
%Y A198364 Cf. A197737.
%K A198364 nonn,cons
%O A198364 0,1
%A A198364 _Clark Kimberling_, Oct 24 2011