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A195706
Decimal expansion of arccos(-sqrt(3/8)).
4
2, 2, 2, 9, 8, 5, 4, 3, 6, 2, 6, 2, 1, 3, 0, 5, 6, 0, 2, 1, 0, 4, 1, 5, 3, 8, 1, 8, 9, 6, 2, 7, 7, 1, 6, 7, 7, 0, 2, 1, 7, 8, 0, 1, 8, 2, 9, 8, 2, 9, 1, 0, 2, 6, 8, 9, 1, 4, 2, 4, 6, 5, 5, 4, 8, 6, 0, 5, 7, 4, 7, 7, 4, 4, 7, 4, 1, 4, 6, 1, 3, 7, 7, 6, 5, 1, 5, 1, 7, 4, 7, 8, 9, 2, 5, 8, 0, 5, 0, 0
OFFSET
1,1
FORMULA
Equals Pi - arcsin(sqrt(5/2)/2) = Pi - arctan(sqrt(5/3)). - Amiram Eldar, Jul 09 2023
EXAMPLE
arccos(-sqrt(3/8)) = 2.2298543626213056...
MATHEMATICA
r = Sqrt[3/8];
N[ArcCos[-r], 100]
RealDigits[%]
PROG
(PARI) acos(-sqrt(3/8)) \\ G. C. Greubel, Aug 19 2018
(Magma) SetDefaultRealField(RealField(100)); Arccos(-Sqrt(3/8)); // G. C. Greubel, Aug 19 2018
CROSSREFS
Cf. A195700.
Sequence in context: A260324 A157649 A155695 * A091185 A372723 A324956
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved