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 A199441 #10 Feb 08 2025 09:17:37
%S A199441 4,7,5,8,6,6,7,2,9,0,6,6,6,2,1,5,0,2,4,7,2,6,1,5,9,3,5,6,1,9,9,6,7,8,
%T A199441 8,9,6,8,0,2,4,4,2,6,3,8,8,7,0,0,4,2,3,3,5,0,8,3,9,5,3,4,2,6,5,5,1,3,
%U A199441 6,2,4,0,7,5,2,8,5,1,4,0,3,7,9,4,5,4,5,3,1,3,0,6,4,7,2,6,0,4,2
%N A199441 Decimal expansion of x>0 satisfying 2*x^2+2*x*sin(x)=cos(x).
%C A199441 See A199370 for a guide to related sequences. The Mathematica program includes a graph.
%H A199441 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199441 0.4758667290666215024726159356199678896802442...
%t A199441 a = 2; b = 2; c = 1;
%t A199441 f[x_] := a*x^2 + b*x*Sin[x]; g[x_] := c*Cos[x]
%t A199441 Plot[{f[x], g[x]}, {x, -Pi, Pi}, {AxesOrigin -> {0, 0}}]
%t A199441 r = x /. FindRoot[f[x] == g[x], {x, .47, .48}, WorkingPrecision -> 110]
%t A199441 RealDigits[r] (* A199441 *)
%Y A199441 Cf. A199429.
%K A199441 nonn,cons
%O A199441 0,1
%A A199441 _Clark Kimberling_, Nov 06 2011