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A200695
Decimal expansion of least x>0 satisfying 1-2*x^2=tan(x).
2
4, 8, 5, 7, 9, 7, 3, 4, 8, 9, 4, 7, 5, 4, 4, 1, 7, 8, 7, 5, 5, 5, 9, 5, 4, 4, 1, 1, 3, 7, 5, 9, 3, 6, 1, 9, 5, 2, 6, 0, 3, 3, 0, 5, 2, 1, 4, 6, 3, 0, 8, 9, 9, 7, 8, 6, 8, 0, 6, 8, 7, 8, 4, 8, 3, 5, 1, 7, 5, 7, 2, 7, 9, 7, 2, 0, 1, 1, 1, 7, 9, 6, 9, 6, 3, 6, 3, 2, 6, 9, 9, 5, 4, 3, 7, 5, 8, 6, 5
OFFSET
0,1
COMMENTS
See A200614 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=0.4857973489475441787555954411375936195260330521...
MATHEMATICA
a = -2; c = 1;
f[x_] := a*x^2 + c; g[x_] := Tan[x]
Plot[{f[x], g[x]}, {x, -.1, Pi/2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, .4, .5}, WorkingPrecision -> 110]
RealDigits[r] (* A200695 *)
CROSSREFS
Cf. A200338.
Sequence in context: A246856 A113969 A155782 * A021677 A124193 A276577
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 21 2011
STATUS
approved