

A222069


Decimal expansion of (1/30)*2^(1/2)*Pi^2.


12



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

0,1


COMMENTS

Conjectured to be 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, What are all the best sphere packings in low dimensions?, Discr. Comp. Geom., 13 (1995), 383403.
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer, 3rd. ed., 1998. See p. xix.


LINKS

Table of n, a(n) for n=0..95.
G. Nebe and N. J. A. Sloane, Home page for D_5 lattice
N. J. A. Sloane, Table of maximal density of a packing of equal spheres in ndimensional Euclidean space (for n>3 the values are only conjectural).
Index entries for transcendental numbers


EXAMPLE

.46525761330925863561050406241129368599465775139653615774...


PROG

(PARI) Pi^2/sqrt(450) \\ Charles R Greathouse IV, Oct 31 2014


CROSSREFS

Related constants: A020769, A020789, A093766, A093825, A222066, A222067, A222068, A222070, A222071, A222072, A222073, A222074, A222075.
Sequence in context: A308716 A021219 A200127 * A274318 A256682 A303404
Adjacent sequences: A222066 A222067 A222068 * A222070 A222071 A222072


KEYWORD

nonn,cons


AUTHOR

N. J. A. Sloane, Feb 10 2013


STATUS

approved



