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 A199871 #10 Feb 08 2025 22:34:45
%S A199871 7,6,6,4,9,1,2,1,3,5,7,0,1,7,9,1,4,9,8,5,2,7,0,4,1,1,4,6,2,4,8,3,7,3,
%T A199871 6,0,4,9,3,0,2,7,0,1,3,9,4,2,2,4,2,9,7,2,0,9,8,9,2,4,1,9,9,7,5,4,6,7,
%U A199871 2,8,7,8,6,5,3,6,3,4,7,3,9,0,5,9,7,7,0,0,7,5,2,7,6,4,5,5,2,8,6,6
%N A199871 Decimal expansion of x > 0 satisfying 4*x^2 - 3*x*cos(x) = sin(x).
%C A199871 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199871 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199871 0.7664912135701791498527041146248373604930270139422...
%t A199871 a = 4; b = -3; c = 1;
%t A199871 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199871 Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]
%t A199871 r = x /. FindRoot[f[x] == g[x], {x, .76, .77}, WorkingPrecision -> 110]
%t A199871 RealDigits[r] (* A199871 *)
%Y A199871 Cf. A199597.
%K A199871 nonn,cons
%O A199871 0,1
%A A199871 _Clark Kimberling_, Nov 11 2011
%E A199871 a(96) onwards corrected by _Georg Fischer_, Aug 03 2021