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 A199453 #8 Feb 08 2025 09:35:24
%S A199453 5,4,1,0,7,0,8,3,0,7,2,2,7,3,2,2,4,3,2,7,3,6,4,5,7,3,9,1,0,9,5,1,7,7,
%T A199453 2,9,9,2,7,9,0,2,7,8,5,3,7,8,9,3,0,7,7,8,6,2,0,3,7,6,2,3,2,0,6,0,7,7,
%U A199453 0,4,4,8,6,7,9,0,1,2,5,4,9,1,3,9,6,1,9,8,4,5,5,8,5,1,3,6,9,2,1
%N A199453 Decimal expansion of x>0 satisfying 3*x^2+3*x*sin(x)=2*cos(x).
%C A199453 See A199370 for a guide to related sequences. The Mathematica program includes a graph.
%H A199453 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199453 0.541070830722732243273645739109517729927902...
%t A199453 a = 3; b = 3; c = 2;
%t A199453 f[x_] := a*x^2 + b*x*Sin[x]; g[x_] := c*Cos[x]
%t A199453 Plot[{f[x], g[x]}, {x, -Pi, Pi}, {AxesOrigin -> {0, 0}}]
%t A199453 r = x /. FindRoot[f[x] == g[x], {x, .54, .55}, WorkingPrecision -> 110]
%t A199453 RealDigits[r] (* A199453 *)
%Y A199453 Cf. A199429.
%K A199453 nonn,cons
%O A199453 0,1
%A A199453 _Clark Kimberling_, Nov 06 2011