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 A199726 #8 Feb 08 2025 22:24:41
%S A199726 1,2,9,2,7,6,2,3,8,4,7,7,3,4,9,5,8,4,6,0,6,7,8,8,8,4,3,5,4,1,5,7,7,9,
%T A199726 4,2,1,7,5,7,9,7,4,4,3,8,5,3,3,8,3,3,0,4,0,0,1,6,5,1,7,8,5,7,9,6,3,9,
%U A199726 9,4,3,6,1,3,5,4,8,4,5,8,8,3,6,6,0,3,3,9,3,1,8,8,8,5,3,3,0,9,7
%N A199726 Decimal expansion of x>0 satisfying x^2-2*x*cos(x)=sin(x).
%C A199726 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199726 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199726 1.29276238477349584606788843541577942175797443...
%t A199726 a = 1; b = -2; c = 1;
%t A199726 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199726 Plot[{f[x], g[x]}, {x, -2 Pi, Pi}, {AxesOrigin -> {0, 0}}]
%t A199726 r = x /. FindRoot[f[x] == g[x], {x, 1.29, 1.30}, WorkingPrecision -> 110]
%t A199726 RealDigits[r] (* A199726 *)
%Y A199726 Cf. A199597.
%K A199726 nonn,cons
%O A199726 1,2
%A A199726 _Clark Kimberling_, Nov 09 2011