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A201678 Decimal expansion of least x satisfying 9*x^2 - 1 = csc(x) and 0<x<Pi. 3
5, 6, 4, 5, 9, 4, 5, 2, 3, 3, 9, 4, 6, 0, 4, 5, 6, 0, 3, 4, 5, 4, 1, 7, 0, 5, 0, 8, 7, 9, 3, 5, 2, 6, 3, 2, 1, 6, 2, 2, 5, 7, 5, 4, 9, 8, 7, 9, 6, 9, 6, 8, 8, 2, 2, 4, 7, 1, 9, 5, 3, 0, 8, 7, 5, 9, 4, 9, 2, 5, 6, 3, 9, 7, 7, 8, 6, 7, 4, 0, 3, 4, 1, 3, 0, 6, 8, 3, 8, 6, 8, 7, 2, 9, 9, 0, 0, 2, 3 (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:  0.5645945233946045603454170508793526321622...

greatest:  3.1301217443279103173861938064228046468...

MATHEMATICA

a = 9; 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, .5, .6}, WorkingPrecision -> 110]

RealDigits[r]     (* A201678 *)

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

RealDigits[r]     (* A201679 *)

PROG

(PARI) a=9; c=-1; solve(x=0.5, 1, a*x^2 + c - 1/sin(x)) \\ G. C. Greubel, Sep 12 2018

CROSSREFS

Cf. A201564.

Sequence in context: A304490 A155591 A152945 * A245870 A343063 A132324

Adjacent sequences:  A201675 A201676 A201677 * A201679 A201680 A201681

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Dec 04 2011

STATUS

approved

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Last modified June 22 21:29 EDT 2021. Contains 345393 sequences. (Running on oeis4.)