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A199269 Decimal expansion of x<0 satisfying 2*x^2+2*x*cos(x)=1. 3
1, 0, 1, 7, 2, 4, 0, 7, 9, 8, 3, 4, 2, 4, 5, 5, 5, 6, 6, 5, 6, 0, 3, 5, 0, 0, 7, 0, 5, 4, 5, 3, 4, 6, 1, 7, 6, 0, 1, 7, 4, 1, 1, 4, 3, 2, 0, 8, 0, 3, 7, 3, 2, 1, 9, 3, 7, 7, 8, 9, 5, 6, 5, 4, 8, 8, 6, 6, 5, 8, 0, 6, 3, 8, 8, 8, 7, 4, 9, 9, 0, 9, 7, 6, 3, 7, 3, 1, 6, 8, 2, 8, 8, 1, 9, 1, 9, 0, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

See A199170 for a guide to related sequences.  The Mathematica program includes a graph.

LINKS

Table of n, a(n) for n=1..99.

EXAMPLE

negative: -1.017240798342455566560350070545346176017411...

positive:  0.381748420992985957918521611823486645593341...

MATHEMATICA

a = 2; b = 2; c = 1;

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

Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]

r = x /. FindRoot[f[x] == g[x], {x, -1.1, -1.0}, WorkingPrecision -> 110]

RealDigits[r]   (* A199269 *)

r = x /. FindRoot[f[x] == g[x], {x, .38, .39}, WorkingPrecision -> 110]

RealDigits[r]   (* A199270 *)

CROSSREFS

Cf. A199170.

Sequence in context: A233929 A241427 A197761 * A021584 A021062 A176436

Adjacent sequences:  A199266 A199267 A199268 * A199270 A199271 A199272

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Nov 04 2011

STATUS

approved

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Last modified December 13 09:48 EST 2019. Contains 329968 sequences. (Running on oeis4.)