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 A198112 #6 Feb 07 2025 16:44:04
%S A198112 8,7,0,3,1,6,3,4,1,1,7,7,4,8,7,5,3,8,6,7,2,4,0,5,2,9,2,3,4,8,1,5,0,6,
%T A198112 1,5,2,5,6,1,6,0,7,0,2,9,9,6,8,3,2,4,5,5,8,8,1,6,7,6,2,7,6,7,6,7,2,5,
%U A198112 5,6,9,1,4,2,2,9,5,1,2,4,2,5,4,7,8,9,3,4,4,4,8,8,5,8,5,3,5,0,8
%N A198112 Decimal expansion of least x having 2*x^2+x=cos(x).
%C A198112 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198112 least x: -0.870316341177487538672405292348150615...
%e A198112 greatest x: 0.4639023825974119097567031695353505...
%t A198112 a = 2; b = 1; c = 1;
%t A198112 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198112 Plot[{f[x], g[x]}, {x, -1, 1}]
%t A198112 r1 = x /. FindRoot[f[x] == g[x], {x, -0.88, -0.87}, WorkingPrecision -> 110]
%t A198112 RealDigits[r1](* A198112 *)
%t A198112 r2 = x /.FindRoot[f[x] == g[x], {x, 4.6, 4.7}, WorkingPrecision -> 110]
%t A198112 RealDigits[r2](* A198113 *)
%Y A198112 Cf. A197737.
%K A198112 nonn,cons
%O A198112 0,1
%A A198112 _Clark Kimberling_, Oct 21 2011