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A195704
Decimal expansion of arccos(-sqrt(1/8)).
2
1, 9, 3, 2, 1, 6, 3, 4, 5, 0, 7, 0, 1, 6, 0, 4, 4, 2, 4, 8, 2, 0, 5, 1, 0, 3, 6, 7, 9, 6, 0, 4, 1, 8, 1, 2, 3, 1, 1, 1, 1, 9, 3, 9, 4, 2, 8, 9, 9, 7, 7, 3, 0, 4, 4, 3, 0, 0, 8, 4, 9, 3, 6, 2, 4, 4, 5, 7, 6, 1, 8, 9, 4, 1, 0, 0, 4, 1, 9, 6, 3, 1, 7, 9, 6, 4, 3, 1, 2, 1, 8, 1, 4, 0, 6, 0, 9, 1, 8, 5
OFFSET
1,2
FORMULA
Equals Pi - arcsin(sqrt(7/2)/2) = Pi - arctan(sqrt(7)). - Amiram Eldar, Jul 09 2023
EXAMPLE
arccos(-sqrt(1/8)) = 1.93216345070...
MATHEMATICA
r = Sqrt[1/8];
N[ArcSin[r], 100]
RealDigits[%] (* A195699 *)
N[ArcCos[r], 100]
RealDigits[%] (* A168229 *)
N[ArcTan[r], 100]
RealDigits[%] (* A188615 *)
N[ArcCos[-r], 100]
RealDigits[%] (* A195704 *)
PROG
(PARI) acos(-sqrt(1/8)) \\ G. C. Greubel, Nov 18 2017
(Magma) [Arccos(-Sqrt(1/8))]; // G. C. Greubel, Nov 18 2017
CROSSREFS
Cf. A195699.
Sequence in context: A086232 A133867 A210113 * A176516 A337768 A372273
KEYWORD
nonn,cons,changed
AUTHOR
Clark Kimberling, Sep 23 2011
STATUS
approved