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 A198345 #9 Feb 07 2025 16:44:05
%S A198345 3,1,0,2,5,9,1,9,1,9,1,8,5,1,0,9,6,0,7,8,1,5,9,5,5,5,9,0,4,4,2,4,2,4,
%T A198345 4,3,9,0,2,4,3,5,6,2,4,7,4,9,9,6,9,6,4,9,6,7,1,4,2,4,6,2,1,0,0,0,7,7,
%U A198345 5,1,5,3,2,2,5,9,1,1,4,0,6,9,7,0,4,5,7,2,9,4,8,7,1,6,7,8,4,4,7,6,7,9
%N A198345 Decimal expansion of least x having 3*x^2-4x=-cos(x).
%C A198345 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198345 least x: 0.310259191918510960781595559044242...
%e A198345 greatest x: 1.2488922646362152688168422541979...
%t A198345 a = 3; b = -4; c = -1;
%t A198345 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198345 Plot[{f[x], g[x]}, {x, -1, 2}]
%t A198345 r1 = x /. FindRoot[f[x] == g[x], {x, -.4, -.3}, WorkingPrecision -> 110]
%t A198345 RealDigits[r1] (* A198345 *)
%t A198345 r2 = x /. FindRoot[f[x] == g[x], {x, 1.24, 1.25}, WorkingPrecision -> 110]
%t A198345 RealDigits[r2] (* A198346 *)
%Y A198345 Cf. A197737.
%K A198345 nonn,cons
%O A198345 0,1
%A A198345 _Clark Kimberling_, Oct 23 2011