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 A198104 #6 Feb 07 2025 16:44:04
%S A198104 2,3,8,8,9,4,9,3,4,3,6,0,8,9,0,4,5,9,6,8,7,0,4,3,2,6,7,8,1,9,7,3,0,9,
%T A198104 9,2,9,6,6,3,3,0,6,0,2,9,4,6,2,2,9,0,1,9,9,1,1,6,9,1,8,0,1,5,0,7,5,0,
%U A198104 6,1,3,9,6,6,1,9,5,3,1,0,8,6,7,7,8,1,1,0,6,0,0,3,7,0,5,5,5,8,6
%N A198104 Decimal expansion of least x having x^2+3x=2*cos(x).
%C A198104 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198104 least x: -2.38894934360890459687043267819730...
%e A198104 greatest x: 0.5010411864464903833151417790663...
%t A198104 a = 1; b = 3; c = 2;
%t A198104 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198104 Plot[{f[x], g[x]}, {x, -3, 1}]
%t A198104 r1 = x /. FindRoot[f[x] == g[x], {x, -2.4, -2.3}, WorkingPrecision -> 110]
%t A198104 RealDigits[r1] (* A198104 *)
%t A198104 r2 = x /. FindRoot[f[x] == g[x], {x, .5, .51}, WorkingPrecision -> 110]
%t A198104 RealDigits[r2] (* A198105 *)
%Y A198104 Cf. A197737.
%K A198104 nonn,cons
%O A198104 1,1
%A A198104 _Clark Kimberling_, Oct 21 2011