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 A199728 #8 Feb 08 2025 22:24:45
%S A199728 1,6,3,5,6,8,8,7,5,1,1,5,4,1,1,0,1,7,9,7,7,8,6,1,4,4,1,8,0,3,7,7,9,0,
%T A199728 9,4,8,4,0,9,9,5,7,9,5,1,2,3,6,0,7,1,2,7,8,3,2,8,3,6,7,8,3,3,6,7,9,0,
%U A199728 7,1,7,4,8,1,6,2,8,8,7,4,5,8,1,5,6,0,2,3,7,3,3,8,9,0,7,7,6,1,8
%N A199728 Decimal expansion of x>0 satisfying x^2-3*x*cos(x)=3*sin(x).
%C A199728 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199728 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199728 1.635688751154110179778614418037790948409...
%t A199728 a = 1; b = -3; c = 3;
%t A199728 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199728 Plot[{f[x], g[x]}, {x, -2 Pi, Pi}, {AxesOrigin -> {0, 0}}]
%t A199728 r = x /. FindRoot[f[x] == g[x], {x, 1.63, 1.64}, WorkingPrecision -> 110]
%t A199728 RealDigits[r] (* A199728 *)
%Y A199728 Cf. A199597.
%K A199728 nonn,cons
%O A199728 1,2
%A A199728 _Clark Kimberling_, Nov 09 2011