A195722 Decimal expansion of arccos(-sqrt(1/6)).

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

Offset: 1

Author

Clark Kimberling, Sep 23 2011

Keywords

• nonn
• cons

Examples

			arccos(-sqrt(1/6)) = 1.99133066207...
		

Links

• G. C. Greubel, Table of n, a(n) for n = 1..10000
• Index entries for transcendental numbers

Crossrefs

Cf. A195720.

Programs

Magma

SetDefaultRealField(RealField(100)); Arccos(-Sqrt(1/6)); // G. C. Greubel, Aug 20 2018

Mathematica

RealDigits[ArcCos[-Sqrt[(1/6)]],10,120][[1]] (* Harvey P. Dale, May 30 2014 *)

PARI

acos(-sqrt(1/6)) \\ G. C. Greubel, Aug 20 2018

Formula

Equals Pi - arcsin(sqrt(5/6)) = Pi - arctan(sqrt(5)). - Amiram Eldar, Jul 06 2023

Extensions

Corrected and extended by Harvey P. Dale, May 30 2014