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A197841 Decimal expansion of least x having x^2+2x=cos(x). 3
1, 8, 5, 0, 7, 1, 7, 4, 4, 1, 5, 6, 1, 9, 8, 2, 9, 0, 1, 2, 9, 7, 8, 7, 8, 8, 3, 1, 4, 5, 8, 8, 7, 4, 4, 9, 2, 3, 9, 5, 6, 3, 3, 6, 9, 1, 3, 7, 1, 4, 2, 8, 7, 9, 1, 6, 1, 7, 6, 9, 7, 0, 2, 3, 2, 0, 9, 6, 1, 4, 6, 7, 3, 5, 0, 9, 4, 6, 9, 2, 9, 6, 0, 2, 4, 5, 4, 8, 8, 9, 3, 2, 3, 3, 7, 3, 4, 3, 2 (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: -1.85071744156198290129787883145887449239...

greatest x: 0.38772212025498533427185200524832923...

MATHEMATICA

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

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, -1.9, -1.8}, WorkingPrecision -> 110]

RealDigits[r1] (* A197841 *)

r2 = x /. FindRoot[f[x] == g[x], {x, .38, .39}, WorkingPrecision -> 110]

RealDigits[r2] (* A197842 *)

CROSSREFS

Cf. A197737.

Sequence in context: A096340 A146489 A230162 * A143347 A073448 A073745

Adjacent sequences:  A197838 A197839 A197840 * A197842 A197843 A197844

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Oct 20 2011

STATUS

approved

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Last modified December 15 20:00 EST 2019. Contains 330000 sequences. (Running on oeis4.)