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A201668 Decimal expansion of least x satisfying 4*x^2 - 1 = csc(x) and 0<x<Pi. 3
7, 7, 8, 4, 7, 6, 7, 7, 7, 2, 7, 7, 5, 9, 4, 2, 3, 1, 2, 9, 0, 0, 3, 5, 2, 7, 9, 9, 8, 6, 7, 2, 6, 8, 7, 7, 9, 8, 6, 1, 2, 4, 8, 6, 5, 6, 2, 6, 2, 4, 6, 1, 1, 5, 6, 8, 0, 0, 6, 2, 0, 9, 6, 5, 7, 7, 6, 3, 2, 2, 1, 7, 5, 3, 8, 6, 6, 8, 9, 4, 8, 6, 1, 4, 6, 8, 3, 7, 2, 9, 9, 1, 2, 4, 5, 4, 7, 3, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

See A201564 for a guide to related sequences.  The Mathematica program includes a graph.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..10000

EXAMPLE

least:  0.7784767772775942312900352799867268779861...

greatest:  3.1151461160403612671519315474503258920...

MATHEMATICA

a = 4; c = -1;

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

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

r = x /. FindRoot[f[x] == g[x], {x, .7, .8}, WorkingPrecision -> 110]

RealDigits[r]     (* A201668 *)

r = x /. FindRoot[f[x] == g[x], {x, 3.0, 3.14}, WorkingPrecision -> 110]

RealDigits[r]     (* A201669 *)

PROG

(PARI) a=4; c=-1; solve(x=0.5, 1, a*x^2 + c - 1/sin(x)) \\ G. C. Greubel, Sep 11 2018

CROSSREFS

Cf. A201564.

Sequence in context: A019718 A316139 A198992 * A021853 A349822 A092616

Adjacent sequences:  A201665 A201666 A201667 * A201669 A201670 A201671

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Dec 04 2011

STATUS

approved

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Last modified January 22 01:28 EST 2022. Contains 350481 sequences. (Running on oeis4.)