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A120671
Decimal expansion of arccos(1-8/(Pi^2)) / (2*Pi).
3
2, 1, 9, 6, 6, 7, 9, 0, 9, 7, 1, 0, 0, 5, 6, 6, 4, 1, 1, 8, 1, 6, 6, 1, 1, 9, 7, 5, 5, 0, 1, 4, 5, 1, 6, 4, 6, 0, 9, 3, 9, 4, 7, 7, 4, 0, 2, 9, 4, 3, 1, 8, 6, 4, 2, 5, 5, 7, 1, 2, 4, 4, 1, 6, 7, 4, 0, 0, 1, 1, 5, 1, 5, 0, 4, 6, 4, 6, 1, 5, 8, 5, 0, 7, 7, 6, 1, 7, 7, 5, 1, 9, 1, 8, 6, 5, 4, 2, 1, 5, 4, 8, 2, 5, 3
OFFSET
0,1
COMMENTS
The average arc length between two randomly chosen points on a circle of radius r is r*A120669 corresponding to the average chord length r*A088538. (Each arc averaged is no larger than the semicircle.). This sequence is the ratio of that average arc length to the circumference (and is thus also the ratio of the corresponding sector's area to the circle's area).
FORMULA
Equals A120669/(2*Pi) = A120670/360.
EXAMPLE
0.219667909710056641181661197550...
MATHEMATICA
RealDigits[ArcCos[(1-(8/(Pi^2) ))]/(2Pi), 10, 120][[1]] (* Harvey P. Dale, Jun 17 2018 *)
PROG
(PARI) acos(1-8/Pi^2)/(2*Pi)
CROSSREFS
Cf. A088538, A120669 (2*Pi*A120671), A120670 (360*A120671).
Sequence in context: A141028 A246323 A201685 * A245461 A086572 A349035
KEYWORD
cons,nonn
AUTHOR
Rick L. Shepherd, Jun 22 2006
STATUS
approved