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 A199622 #8 Feb 08 2025 22:13:57
%S A199622 5,2,1,7,7,0,5,3,3,6,3,0,4,1,5,9,0,7,6,0,2,2,2,6,7,1,7,5,2,3,9,3,7,8,
%T A199622 8,2,9,5,7,5,1,0,8,9,8,0,1,9,0,1,6,1,5,6,1,5,0,9,6,0,0,6,2,7,2,1,1,0,
%U A199622 4,7,2,8,7,3,1,4,9,5,9,6,8,5,8,0,7,2,5,8,7,8,1,8,9,8,2,5,1,8,2
%N A199622 Decimal expansion of x>0 satisfying 2*x^2+x*cos(x)=2*sin(x).
%C A199622 See A199597 for a guide to related sequences. The Mathematica program includes a graph.
%H A199622 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199622 0.521770533630415907602226717523937882...
%t A199622 a = 2; b = 1; c = 2;
%t A199622 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
%t A199622 Plot[{f[x], g[x]}, {x, -3, 2}, {AxesOrigin -> {0, 0}}]
%t A199622 r = x /. FindRoot[f[x] == g[x], {x, .52, .53}, WorkingPrecision -> 110]
%t A199622 RealDigits[r] (* A199622 *)
%Y A199622 Cf. A199597.
%K A199622 nonn,cons
%O A199622 0,1
%A A199622 _Clark Kimberling_, Nov 08 2011