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 A199783 #8 Feb 08 2025 22:30:17
%S A199783 1,3,1,6,1,8,8,8,7,0,7,7,3,5,2,8,4,8,6,8,5,0,0,1,0,8,0,6,8,9,9,2,2,1,
%T A199783 1,4,5,2,8,1,0,0,1,6,5,0,0,5,0,7,2,9,0,0,8,3,0,7,1,3,9,9,6,0,5,6,4,2,
%U A199783 3,9,5,3,4,1,3,2,2,8,0,5,3,4,0,7,2,8,1,2,1,7,3,4,8,6,3,2,4,2,4
%N A199783 Decimal expansion of x>0 satisfying 3*x^2-4*x*cos(x)=-4*sin(x).
%C A199783 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199783 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199783 1.316188870773528486850010806899221145281001...
%t A199783 a = 3; b = -4; c = 4;
%t A199783 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199783 Plot[{f[x], g[x]}, {x, -1, 2}, {AxesOrigin -> {0, 0}}]
%t A199783 r = x /. FindRoot[f[x] == g[x], {x, 1.31, 1.32}, WorkingPrecision -> 110]
%t A199783 RealDigits[r] (* A199783 *)
%Y A199783 Cf. A199597.
%K A199783 nonn,cons
%O A199783 1,2
%A A199783 _Clark Kimberling_, Nov 10 2011