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 A197845 #6 Feb 07 2025 16:44:04
%S A197845 1,7,2,8,0,7,8,0,8,6,2,5,3,1,4,2,1,7,1,3,9,7,2,4,5,4,3,2,4,2,4,7,6,8,
%T A197845 2,6,7,7,6,2,0,8,0,6,2,0,8,4,3,1,3,3,5,4,1,6,2,6,1,2,4,2,5,1,3,8,6,4,
%U A197845 1,6,9,0,4,2,6,1,7,0,0,3,8,7,3,5,0,7,3,9,8,9,6,7,6,4,8,6,2,4,4
%N A197845 Decimal expansion of least x having x^2+2x=3*cos(x).
%C A197845 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A197845 least x: -1.72807808625314217139724543242476826...
%e A197845 greatest x: 0.773696189243809421714739053530453...
%t A197845 a = 1; b = 2; c = 3;
%t A197845 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A197845 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A197845 r1 = x /. FindRoot[f[x] == g[x], {x, -1.8, -1.7}, WorkingPrecision -> 110]
%t A197845 RealDigits[r1] (* A197845 *)
%t A197845 r2 = x /. FindRoot[f[x] == g[x], {x, .77, .78}, WorkingPrecision -> 110]
%t A197845 RealDigits[r2] (* A197846 *)
%Y A197845 Cf. A197737.
%K A197845 nonn,cons
%O A197845 1,2
%A A197845 _Clark Kimberling_, Oct 20 2011