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A195698
Decimal expansion of arccos(-sqrt(1/3)).
2
2, 1, 8, 6, 2, 7, 6, 0, 3, 5, 4, 6, 5, 2, 8, 3, 9, 6, 0, 2, 9, 8, 7, 8, 6, 2, 8, 0, 7, 6, 3, 7, 4, 5, 1, 2, 9, 9, 5, 3, 7, 5, 4, 7, 0, 4, 3, 6, 5, 1, 0, 0, 3, 3, 0, 0, 1, 5, 2, 4, 6, 4, 6, 2, 9, 8, 5, 9, 0, 4, 3, 6, 0, 3, 8, 2, 2, 3, 2, 5, 4, 3, 2, 4, 0, 6, 4, 3, 2, 2, 2, 7, 5, 6, 4, 8, 8, 9, 9, 4
OFFSET
1,1
COMMENTS
Dihedral angle between mixed type faces of the truncated octahedron. - R. J. Mathar, Mar 24 2012
LINKS
FORMULA
Equals Pi - arcsin(sqrt(2/3)) = Pi - arctan(sqrt(2)). - Amiram Eldar, Jul 08 2023
EXAMPLE
arccos(-1/sqrt(3)) = 2.1862760354...
MATHEMATICA
(See A195695.)
RealDigits[ArcCos[-1/Sqrt[3]], 10, 50][[1]] (* G. C. Greubel, Nov 18 2017 *)
PROG
(PARI) acos(-1/sqrt(3)) \\ G. C. Greubel, Nov 18 2017
(Magma) [Arccos(-1/Sqrt(3))]; // G. C. Greubel, Nov 18 2017
CROSSREFS
Cf. A195695.
Sequence in context: A108084 A305860 A272983 * A193908 A193904 A154897
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved