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%I #8 Aug 09 2021 08:08:21
%S 2,1,8,3,6,5,7,8,0,2,7,1,6,2,3,8,6,5,1,6,7,8,7,8,8,2,4,5,4,8,0,9,0,3,
%T 6,6,5,8,9,1,2,2,3,1,5,2,8,1,4,4,7,3,4,1,9,6,9,7,7,8,0,8,7,3,8,1,4,8,
%U 1,8,8,9,8,0,6,6,6,5,3,2,8,5,9,3,7,4,7,6,4,1,5,7,3,9,6,9,7,4,6,6,8
%N Decimal expansion of least x>0 satisfying 2*x^2-4*x+1=tan(x).
%C See A200338 for a guide to related sequences. The Mathematica program includes a graph.
%e x=0.21836578027162386516787882454809036658912231...
%t a = 2; b = -4; c = 1;
%t f[x_] := a*x^2 + b*x + c; g[x_] := Tan[x]
%t Plot[{f[x], g[x]}, {x, -.1, Pi/2}, {AxesOrigin -> {0, 0}}]
%t r = x /. FindRoot[f[x] == g[x], {x, .2, .3}, WorkingPrecision -> 110]
%t RealDigits[r] (* A200584 *)
%Y Cf. A200338.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Nov 19 2011