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A198884 Decimal expansion of x>0 satisfying 2*x^2-4*cos(x)=-1. 2
8, 7, 9, 9, 7, 0, 4, 0, 3, 2, 4, 2, 3, 9, 4, 2, 3, 8, 7, 9, 6, 3, 1, 5, 3, 4, 4, 0, 5, 3, 6, 4, 4, 3, 8, 3, 9, 3, 8, 7, 1, 8, 2, 8, 8, 5, 4, 4, 9, 7, 2, 8, 4, 9, 9, 3, 3, 2, 2, 4, 9, 1, 0, 0, 1, 9, 1, 6, 5, 6, 1, 6, 6, 9, 7, 8, 9, 9, 2, 1, 2, 1, 5, 9, 3, 5, 4, 2, 3, 9, 7, 7, 6, 9, 9, 5, 7, 3, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

See A198755 for a guide to related sequences.  The Mathematica program includes a graph.

LINKS

Table of n, a(n) for n=0..98.

EXAMPLE

x=0.8799704032423942387963153440536443839...

MATHEMATICA

a = 2; b = -4; c = -1;

f[x_] := a*x^2 + b*Cos[x]; g[x_] := c

Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]

r = x /. FindRoot[f[x] == g[x], {x, .87, .88}, WorkingPrecision -> 110]

RealDigits[r] (* A198884 *)

CROSSREFS

Cf. A198755.

Sequence in context: A197688 A094082 A318378 * A212911 A019326 A286839

Adjacent sequences:  A198881 A198882 A198883 * A198885 A198886 A198887

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 31 2011

STATUS

approved

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Last modified February 18 10:22 EST 2019. Contains 320250 sequences. (Running on oeis4.)