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Constructive packings of cross polytopes

Published online by Cambridge University Press:  26 February 2010

J. A. Rush
Affiliation:
Professor J. A. Rush, Department of Mathematics, GN-50, University of Washington, Seattle, Washington 98195, U.S.A.
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Abstract

The n-dimensional cross polytope, |x|+|x2|+…+|xn≤1, can be lattice packed with density δ satisfying

but proofs of this, such as the Minkowski-Hlawka theorem, do not actually provide such packings. That is, they are nonconstructive. Here we exhibit lattice packings whose density satisfies only

but by a highly constructive method. These are the densest constructive lattice packings of cross polytopes obtained so far.

MSC classification

Type
Research Article
Copyright
Copyright © University College London 1991

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References

1.Barnes, E. S. and Sloane, N. J. A.. New lattice packings of spheres. Canad. J. Math., 35 (1983), 117130.CrossRefGoogle Scholar
2.Barnes, E. S. and Wall, G. E.. Some extreme forms denned in terms of Abelian groups. J. Am. Math. Soc, 1 (1959), 4763.Google Scholar
3.Berlekamp, E. R.. Algebraic Coding Theory (McGraw-Hill, N.Y., 1968).Google Scholar
4.Cassels, J. W. S.. An Introduction to the Geometry of Numbers (Springer-Verlag, N.Y., second printing, 1971).Google Scholar
5.Conway, J. H. and Sloane, N. J. A.. Sphere Packings, Lattices and Groups (Springer-Verlag, N.Y., 1987).Google Scholar
6.Elkies, N. D., Odlyzko, A. M. and Rush, J. A.. On the packing densities of superballs and other bodies. Invent, math., 105 (1991), 613639.CrossRefGoogle Scholar
7.Erdös, P., Gruber, P. M. and Hammer, J.. Lattice Points Pitman Monograph 39 (Longman Scientific, N.Y., 1989).Google Scholar
8.Gruber, P. M. and Lekkerkerker, C. G.. Geometry of Numbers (Elsevier, North-Holland, Amsterdam, 1987).Google Scholar
9.Hlawka, E.. Zur Geometrie de Zahlen. Math. Zeitschr., 49 (1943), 285312.CrossRefGoogle Scholar
10.Lee, C. Y.. Some Properties of Nonbinary Error-correcting Codes, IEEE Trans. Inform. Theory, IT4, 7782 (1958).CrossRefGoogle Scholar
11.Leech, J. and Sloane, N. J. A.. Sphere packing and error-correcting codes, Canad, J. Math., 23 (1971), 718745.CrossRefGoogle Scholar
12.Litsyn, S. N. and Tsfasman, M. A.. Algebraic-geometric and number-theoretic packings of spheres (in Russian), Uspekhi Mat. Nauk, 40 (1985), 185186.Google Scholar
13.Litsyn, S. N. and Tsfasman, M. A.. Constructive high-dimensional sphere packings, Duke Math. J., 54 (1987), 147161.CrossRefGoogle Scholar
14.Rogers, C. A.. Packing and Covering, Cambridge University Press, 1964.Google Scholar
15.Rush, J. A. and Sloane, N. J. A.. An improvement to the Minkowski-Hlawka bound for packing superballs, Mathematika, 34 (1987), 818.CrossRefGoogle Scholar
16.Rush, J. A.. A lower bound on packing density, Invent, math., 98 (1989), 499509.CrossRefGoogle Scholar
17.Rush, J. A.. Thin lattice coverings, J. London Math. Soc, to appear.Google Scholar