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A198139 Decimal expansion of greatest x having 3*x^2+4x=4*cos(x). 3
5, 8, 1, 7, 2, 0, 0, 7, 9, 7, 3, 1, 6, 5, 9, 7, 2, 2, 8, 4, 2, 8, 6, 5, 9, 2, 3, 2, 7, 1, 4, 8, 8, 2, 7, 4, 9, 0, 7, 5, 9, 9, 1, 9, 8, 4, 9, 2, 8, 9, 2, 5, 9, 8, 6, 9, 8, 4, 4, 3, 4, 7, 2, 5, 8, 1, 1, 3, 0, 3, 7, 5, 4, 1, 9, 5, 2, 2, 4, 1, 8, 7, 9, 2, 9, 8, 8, 4, 1, 3, 4, 0, 5, 2, 8, 0, 4, 1, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

See A197737 for a guide to related sequences.  The Mathematica program includes a graph.

LINKS

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

EXAMPLE

least x: -1.447057151041655078779471681449880627...

greatest x: 0.58172007973165972284286592327148827490...

MATHEMATICA

a = 3; b = 4; c = 4;

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

Plot[{f[x], g[x]}, {x, -2, 1}]

r1 = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.4}, WorkingPrecision -> 110]

RealDigits[r1] (* A198138 *)

r2 = x /. FindRoot[f[x] == g[x], {x, .58, .59}, WorkingPrecision -> 110]

RealDigits[r2] (* A198139 *)

CROSSREFS

Cf. A197737.

Sequence in context: A193743 A195356 A263497 * A247277 A171709 A093157

Adjacent sequences:  A198136 A198137 A198138 * A198140 A198141 A198142

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 23 2011

STATUS

approved

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Last modified January 23 03:15 EST 2022. Contains 350504 sequences. (Running on oeis4.)