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A222066
Decimal expansion of 1/sqrt(128).
11
0, 8, 8, 3, 8, 8, 3, 4, 7, 6, 4, 8, 3, 1, 8, 4, 4, 0, 5, 5, 0, 1, 0, 5, 5, 4, 5, 2, 6, 3, 1, 0, 6, 1, 2, 9, 9, 1, 0, 6, 0, 4, 4, 9, 2, 2, 1, 1, 0, 5, 9, 2, 5, 4, 5, 7, 3, 5, 4, 2, 4, 8, 3, 6, 2, 4, 4, 2, 0, 7, 7, 9, 9, 0, 3, 8, 8, 1, 6, 8, 9, 9, 2, 8, 1, 4, 9, 2, 2, 0, 8, 9, 5, 4, 7, 7, 5, 9, 8, 2, 9, 5, 9, 3, 8
OFFSET
0,2
COMMENTS
Conjectured to be center density of densest packing of equal spheres in five dimensions (achieved for example by the D_5 lattice).
REFERENCES
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer, 3rd. ed., 1998. See p. xix.
FORMULA
Equals A020789/2. - R. J. Mathar, Jan 27 2021
EXAMPLE
.088388347648318440550105545263106129910604492211...
MATHEMATICA
Join[{0}, RealDigits[1/Sqrt[128], 10, 120][[1]]] (* Harvey P. Dale, Sep 20 2023 *)
PROG
(PARI) 1/sqrt(128) \\ Charles R Greathouse IV, Oct 31 2014
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
N. J. A. Sloane, Feb 10 2013
STATUS
approved