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A198138 Decimal expansion of least x having 3*x^2+4x=4*cos(x). 3
1, 4, 4, 7, 0, 5, 7, 1, 5, 1, 0, 4, 1, 6, 5, 5, 0, 7, 8, 7, 7, 9, 4, 7, 1, 6, 8, 1, 4, 4, 9, 8, 8, 0, 6, 2, 7, 5, 0, 5, 7, 7, 2, 9, 3, 2, 5, 5, 0, 6, 3, 6, 8, 9, 6, 4, 8, 9, 5, 3, 3, 6, 2, 9, 5, 4, 9, 4, 1, 3, 3, 4, 8, 1, 0, 8, 7, 4, 9, 3, 3, 3, 4, 4, 2, 9, 6, 6, 7, 5, 8, 2, 5, 8, 1, 5, 7, 7, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

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

EXAMPLE

least x: -1.447057151041655078779471681449880627...

greatest x: 0.5817200797316597228428659232714882...

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: A264578 A261146 A090531 * A300709 A240924 A319034

Adjacent sequences:  A198135 A198136 A198137 * A198139 A198140 A198141

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 23 2011

STATUS

approved

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Last modified December 2 18:41 EST 2021. Contains 349445 sequences. (Running on oeis4.)