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A200697
Decimal expansion of least x>0 satisfying 1-3*x^2=tan(x).
2
4, 2, 6, 4, 7, 3, 8, 7, 2, 8, 0, 9, 1, 4, 5, 1, 3, 2, 9, 9, 5, 2, 9, 9, 1, 3, 5, 6, 3, 2, 8, 0, 1, 9, 1, 2, 1, 2, 8, 7, 1, 0, 3, 7, 7, 5, 9, 4, 7, 2, 9, 3, 3, 3, 9, 4, 8, 1, 0, 1, 8, 9, 3, 3, 6, 8, 1, 6, 0, 9, 1, 2, 5, 9, 4, 2, 7, 5, 8, 3, 3, 5, 2, 1, 5, 8, 5, 5, 7, 5, 4, 1, 2, 6, 6, 0, 6, 3, 5
OFFSET
0,1
COMMENTS
See A200614 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=0.426473872809145132995299135632801912128710...
MATHEMATICA
a = -3; 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] (* A200697 *)
CROSSREFS
Cf. A200338.
Sequence in context: A138614 A161912 A162339 * A253629 A327095 A176836
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 21 2011
STATUS
approved