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 A198212 #6 Feb 07 2025 16:44:05
%S A198212 7,1,0,7,9,4,6,8,7,7,7,4,4,6,5,3,3,7,8,4,6,7,3,5,2,9,1,4,7,5,3,2,7,5,
%T A198212 9,4,3,3,2,3,7,4,4,0,8,7,1,7,6,4,0,0,4,0,2,2,4,3,3,1,6,6,1,9,5,3,8,0,
%U A198212 2,0,4,7,2,3,1,7,4,4,8,3,4,5,1,0,6,0,6,4,8,9,0,1,9,2,3,9,8,8,3
%N A198212 Decimal expansion of x>0 having 3*x^2=2*cos(x).
%C A198212 See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e A198212 x=0.7107946877744653378467352914753275...
%t A198212 a = 3; b = 0; c = 2;
%t A198212 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A198212 Plot[{f[x], g[x]}, {x, -1, 1}]
%t A198212 r = x /. FindRoot[f[x] == g[x], {x, 0.71, 0.72}, WorkingPrecision -> 110]
%t A198212 RealDigits[r] (* A198212 *)
%Y A198212 Cf. A197737.
%K A198212 nonn,cons
%O A198212 0,1
%A A198212 _Clark Kimberling_, Oct 22 2011