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 A199625 #8 Feb 08 2025 22:14:02
%S A199625 4,2,5,7,1,1,4,2,3,2,3,6,2,8,2,9,5,5,0,2,7,8,5,0,2,3,0,7,9,0,3,4,1,3,
%T A199625 2,6,9,2,8,6,5,8,1,3,7,3,5,0,8,9,3,7,8,2,7,7,8,7,8,9,7,7,8,4,6,8,1,5,
%U A199625 7,1,1,7,1,9,8,7,5,4,7,7,3,9,5,2,5,2,4,6,5,2,0,7,8,3,7,5,9,6,1
%N A199625 Decimal expansion of x<0 satisfying 2*x^2+2*x*cos(x)=sin(x).
%C A199625 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199625 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199625 -0.425711423236282955027850230790341326928658...
%t A199625 a = 2; b = 2; c = 1;
%t A199625 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199625 Plot[{f[x], g[x]}, {x, -Pi, Pi}, {AxesOrigin -> {0, 0}}]
%t A199625 r = x /. FindRoot[f[x] == g[x], {x, -.43, -.42}, WorkingPrecision -> 110]
%t A199625 RealDigits[r] (* A199625 *)
%Y A199625 Cf. A199597.
%K A199625 nonn,cons
%O A199625 0,1
%A A199625 _Clark Kimberling_, Nov 09 2011