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Decimal expansion of least x>0 satisfying 1-5*x^2=tan(x).
2

%I #5 Mar 30 2012 18:58:01

%S 3,5,4,8,2,2,8,6,5,9,8,5,9,9,0,7,5,7,7,7,6,5,2,8,8,7,1,9,5,0,1,3,6,8,

%T 4,3,4,1,5,2,4,2,4,1,9,2,4,5,4,3,8,1,1,1,8,2,2,3,5,1,3,5,5,8,6,8,2,5,

%U 8,8,9,5,3,2,5,9,3,4,8,8,7,1,6,3,5,5,1,4,4,0,2,0,7,1,0,3,0,0,2

%N Decimal expansion of least x>0 satisfying 1-5*x^2=tan(x).

%C See A200614 for a guide to related sequences. The Mathematica program includes a graph.

%e x=0.3548228659859907577765288719501368434152424...

%t a = -5; c = 1;

%t f[x_] := a*x^2 + 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, .3, .4}, WorkingPrecision -> 110]

%t RealDigits[r] (* A200700 *)

%Y Cf. A200338.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Nov 21 2011