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 A198120 #7 Feb 07 2025 16:44:04
%S A198120 4,2,3,4,1,8,8,6,7,4,3,6,9,5,6,3,9,0,2,5,4,9,0,1,9,1,4,5,6,7,1,3,7,9,
%T A198120 8,7,7,8,8,8,1,6,9,1,7,2,9,9,4,8,0,6,3,4,0,9,5,8,5,0,6,3,0,6,0,5,6,7,
%U A198120 1,3,8,3,3,0,6,0,1,9,8,2,1,5,8,2,0,6,1,7,4,1,3,1,2,5,8,5,7,1,2
%N A198120 Decimal expansion of least x having 2*x^2-3x=-cos(x).
%C A198120 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198120 least x: 0.42341886743695639025490191456713...
%e A198120 greatest x: 1.46336282729643114510529642616...
%t A198120 a = 2; b = -3; c = -1;
%t A198120 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198120 Plot[{f[x], g[x]}, {x, -1, 2}]
%t A198120 r1 = x /. FindRoot[f[x] == g[x], {x, -.43, -.42}, WorkingPrecision -> 110]
%t A198120 RealDigits[r1](* A198120 *)
%t A198120 r2 = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
%t A198120 RealDigits[r2](* A198121 *)
%Y A198120 Cf. A197737.
%K A198120 nonn,cons
%O A198120 0,1
%A A198120 _Clark Kimberling_, Oct 21 2011