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A197840 Decimal expansion of greatest x having x^2-4x=-cos(x). 3
4, 1, 3, 2, 5, 7, 3, 4, 7, 0, 7, 5, 3, 8, 6, 8, 3, 0, 8, 1, 9, 8, 4, 4, 1, 7, 0, 5, 3, 6, 2, 8, 0, 6, 1, 2, 1, 0, 5, 5, 1, 8, 5, 3, 1, 5, 3, 8, 1, 1, 1, 8, 0, 1, 1, 7, 2, 6, 0, 4, 0, 6, 9, 4, 2, 3, 3, 7, 8, 0, 0, 3, 2, 1, 2, 4, 7, 6, 1, 8, 2, 7, 0, 6, 7, 2, 4, 2, 3, 5, 8, 4, 3, 9, 1, 8, 1, 4, 3 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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: 0.25839214437159967402757423807386027526101...

greatest x: 4.13257347075386830819844170536280612105...

MATHEMATICA

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

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

Plot[{f[x], g[x]}, {x, -1, 5}]

r1 = x /. FindRoot[f[x] == g[x], {x, -4.2, -4.1}, WorkingPrecision -> 110]

RealDigits[r1] (* A197839 *)

r2 = x /. FindRoot[f[x] == g[x], {x, 4.1, 4.2}, WorkingPrecision -> 110]

RealDigits[r2] (* A197840 *)

CROSSREFS

Cf. A197737.

Sequence in context: A327357 A021246 A301907 * A019633 A067277 A177951

Adjacent sequences:  A197837 A197838 A197839 * A197841 A197842 A197843

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 20 2011

STATUS

approved

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Last modified December 8 18:37 EST 2019. Contains 329865 sequences. (Running on oeis4.)