A019702 Decimal expansion of 2*Pi/21.

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

Offset

0,1

Comments

Pi/105 = 0.1 * 2*Pi/21 is the mean area of the triangles that can be formed by breaking a unit-length stick in 3 parts, by uniformly and independently choosing 2 points on it (taking only those cases in which the 3 parts can form a triangle) (Mathai, 1999). - Amiram Eldar, Jul 28 2020

References

A. M. Mathai, An Introduction to Geometrical Probability: Distributional Aspects with Applications, CRC Press, 1999. See example 2.5.3, pp. 269-270.

Links

Ivan Panchenko, Table of n, a(n) for n = 0..1000

Index entries for transcendental numbers

Example

0.299199300341885070329775560312333608018778038035724...

Mathematica

RealDigits[2*Pi/21, 10, 100][[1]] (* Amiram Eldar, Jul 28 2020 *)

Prog

(PARI) 2*Pi/21 \\ Charles R Greathouse IV, Oct 01 2022

Crossrefs

Equals twice A019688.

Cf. A000796.

Sequence in context: A340723 A201765 A160331 * A201899 A201894 A023400

Adjacent sequences: A019699 A019700 A019701 * A019703 A019704 A019705

Keyword

nonn,cons

Author

N. J. A. Sloane.

Status

approved