A201588 Decimal expansion of greatest x satisfying 4*x^2 = csc(x) and 0 < x < Pi.

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

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:  0.6448974755436738344433573900444745201701368...
greatest:  3.1158390512762535211310850151952082587811...

Mathematica

a = 4; c = 0;
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, .6, .7}, WorkingPrecision -> 110]
RealDigits[r]   (* A201587 *)
r = x /. FindRoot[f[x] == g[x], {x, 3.1, 3.14}, WorkingPrecision -> 110]
RealDigits[r]   (* A201588 *)

Prog

(PARI) a=4; c=0; solve(x=3.1, 3.14, a*x^2 + c - 1/sin(x)) \\ G. C. Greubel, Aug 22 2018

Crossrefs

Cf. A201564.

Sequence in context: A118538 A141523 A285808 * A336858 A086385 A295222

Adjacent sequences: A201585 A201586 A201587 * A201589 A201590 A201591

Keyword

nonn,cons

Author

Clark Kimberling, Dec 03 2011

Status

approved