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A019696
Decimal expansion of 2*Pi/9.
1
6, 9, 8, 1, 3, 1, 7, 0, 0, 7, 9, 7, 7, 3, 1, 8, 3, 0, 7, 6, 9, 4, 7, 6, 3, 0, 7, 3, 9, 5, 4, 4, 5, 0, 8, 5, 3, 7, 7, 1, 4, 8, 7, 5, 5, 4, 1, 6, 6, 9, 0, 1, 8, 2, 4, 3, 8, 8, 7, 6, 5, 7, 6, 0, 6, 8, 4, 0, 3, 6, 4, 5, 8, 4, 1, 3, 7, 9, 7, 7, 7, 4, 7, 2, 8, 9, 6, 6, 2, 7, 8, 5, 3, 8, 0, 3, 7, 9, 2
OFFSET
0,1
COMMENTS
The area of a deltoid formed by rolling a circle with radius 1/3 inside a unit-radius circle. - Amiram Eldar, Nov 16 2021
Volume shared by a sphere of radius 1 inscribed in a cube and one of the six pyramids inscribed in the cube. - Omar E. Pol, Sep 01 2024
LINKS
Eric Weisstein's World of Mathematics, Deltoid.
EXAMPLE
0.69813170079773183076947630739544508537714875541669...
MATHEMATICA
RealDigits[(2*Pi)/9, 10, 120][[1]] (* Harvey P. Dale, Aug 24 2013 *)
PROG
(PARI) 2*Pi/9 \\ Michel Marcus, Nov 16 2021
CROSSREFS
Equals twice A019676.
Sequence in context: A371134 A344083 A375594 * A119801 A191608 A266563
KEYWORD
nonn,cons
AUTHOR
STATUS
approved