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 A199739 #11 Feb 08 2025 22:25:31
%S A199739 1,4,4,0,9,8,5,1,6,3,2,1,0,3,7,3,7,7,8,4,5,1,3,8,0,4,5,4,2,3,4,8,2,8,
%T A199739 4,2,7,0,0,4,4,4,9,0,2,5,8,2,4,3,7,6,1,9,4,5,8,1,2,3,9,0,7,5,8,1,0,0,
%U A199739 9,0,6,8,5,1,7,2,3,1,6,1,3,5,1,8,1,2,2,7,6,6,1,9,1,2,4,3,4,4,9
%N A199739 Decimal expansion of x>0 satisfying 2*x^2-x*cos(x)=4*sin(x).
%C A199739 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199739 Matthew House, <a href="/A199739/b199739.txt">Table of n, a(n) for n = 1..10000</a>
%H A199739 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199739 1.44098516321037377845138045423482842700444...
%t A199739 a = 2; b = -1; c = 4;
%t A199739 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199739 Plot[{f[x], g[x]}, {x, -1, 2}, {AxesOrigin -> {0, 0}}]
%t A199739 r = x /. FindRoot[f[x] == g[x], {x, 1.44, 1.45}, WorkingPrecision -> 110]
%t A199739 RealDigits[r] (* A199739 *)
%Y A199739 Cf. A199597.
%K A199739 nonn,cons
%O A199739 1,2
%A A199739 _Clark Kimberling_, Nov 10 2011
%E A199739 Definition corrected by _Matthew House_, Dec 24 2016