A195731 Decimal expansion of arcsec(4).

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

Offset

1,2

Links

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

Formula

Equals arcsin(sqrt(15)/4) = arccos(1/4) = arctan(sqrt(15)). - Amiram Eldar, May 24 2021

Example

arcsec(4) = 1.318116071652817965...

Mathematica

r=4;
N[ArcSec[r], 100]
RealDigits[%]

Prog

(PARI) acos(1/4) \\ G. C. Greubel, Aug 20 2018
(Magma) SetDefaultRealField(RealField(100)); Arccos(1/4); // G. C. Greubel, Aug 20 2018

Crossrefs

Cf. A195628.

Sequence in context: A141252 A276168 A165498 * A331187 A154294 A059526

Adjacent sequences: A195728 A195729 A195730 * A195732 A195733 A195734

Keyword

nonn,cons

Author

Clark Kimberling, Sep 23 2011

Status

approved