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A199188 Decimal expansion of x<0 satisfying 2*x^2+x*cos(x)=1. 4
8, 8, 3, 3, 3, 0, 1, 9, 7, 1, 9, 5, 8, 9, 1, 9, 3, 8, 9, 2, 5, 8, 9, 6, 4, 5, 0, 8, 8, 5, 6, 7, 7, 1, 0, 7, 2, 3, 5, 0, 5, 9, 0, 0, 8, 8, 4, 2, 3, 1, 8, 8, 2, 3, 1, 6, 6, 7, 6, 3, 6, 6, 7, 3, 1, 6, 3, 4, 3, 1, 9, 5, 8, 7, 3, 3, 2, 2, 6, 1, 2, 9, 9, 8, 7, 3, 3, 1, 6, 8, 8, 3, 1, 9, 8, 3, 3, 3, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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: -0.883330197195891938925896450885677107...

positive:  0.522945946113111737247623836359811237...

MATHEMATICA

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

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

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

r = x /. FindRoot[f[x] == g[x], {x, -.84, -.83}, WorkingPrecision -> 110]

RealDigits[r]  (* A199188 *)

r = x /. FindRoot[f[x] == g[x], {x, .52, .53}, WorkingPrecision -> 110]

RealDigits[r]  (*  A199189 *)

CROSSREFS

Cf. A199170.

Sequence in context: A010530 A289915 A021535 * A254291 A219300 A200686

Adjacent sequences:  A199185 A199186 A199187 * A199189 A199190 A199191

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Nov 04 2011

STATUS

approved

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Last modified February 24 07:19 EST 2020. Contains 332199 sequences. (Running on oeis4.)