A201679 Decimal expansion of greatest x satisfying 9*x^2 - 1 = csc(x) and 0<x<Pi.

3, 1, 3, 0, 1, 2, 1, 7, 4, 4, 3, 2, 7, 9, 1, 0, 3, 1, 7, 3, 8, 6, 1, 9, 3, 8, 0, 6, 4, 2, 2, 8, 0, 4, 6, 4, 6, 8, 7, 3, 8, 2, 7, 3, 1, 0, 5, 6, 8, 6, 3, 4, 8, 6, 1, 1, 4, 2, 4, 1, 0, 1, 2, 3, 8, 5, 4, 7, 6, 3, 5, 5, 9, 9, 3, 5, 9, 7, 7, 8, 2, 7, 4, 2, 0, 6, 1, 6, 3, 8, 9, 3, 5, 2, 0, 2, 2, 5, 9

Offset

1,1

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 = 1..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=3, 3.14, a*x^2 + c - 1/sin(x)) \\ G. C. Greubel, Sep 12 2018

Crossrefs

Cf. A201564.

Sequence in context: A146524 A179656 A167274 * A131088 A136157 A266260

Adjacent sequences: A201676 A201677 A201678 * A201680 A201681 A201682

Keyword

nonn,cons

Author

Clark Kimberling, Dec 04 2011

Status

approved