A195711 Decimal expansion of arccos(-sqrt(5/8)).

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

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..10000

Formula

Equals Pi - arcsin(sqrt(3/8)) = Pi - arctan(sqrt(3/5)). - Amiram Eldar, Jul 06 2023

Example

2.48253461776338...

Mathematica

(See A195707.)
RealDigits[ArcCos[-Sqrt[(5/8)]], 10, 120][[1]] (* Harvey P. Dale, Mar 12 2013 *)

Prog

(PARI) acos(-sqrt(5/8)) \\ G. C. Greubel, Aug 19 2018
(Magma) SetDefaultRealField(RealField(100)); Arccos(-Sqrt(5/8)); // G. C. Greubel, Aug 19 2018

Crossrefs

Cf. A195707.

Sequence in context: A175131 A033921 A167420 * A200610 A076232 A011032

Adjacent sequences: A195708 A195709 A195710 * A195712 A195713 A195714

Keyword

nonn,cons

Author

Clark Kimberling, Sep 23 2011

Status

approved