A065536 Number of strongly eutactic lattices in dimension n.

1, 2, 3, 6, 9, 21

Offset

1,2

References

J. Martinet, Les reseaux parfaits des espaces Euclidiens, Masson, Paris, 1996.

J. Martinet, Perfect Lattices in Euclidean Spaces, Springer-Verlag, NY, 2003.

G. Nebe, Review of J. Martinet, Perfect Lattices in Euclidean Spaces, Bull. Amer. Math. Soc., 41 (No. 4, 2004), 529-533.

Links

Table of n, a(n) for n=1..6.

Christian Batut and Jacques Martinet, Lattices and spherical designs, 2005-2014. See pages 12-13.

J. Martinet and B. Venkov, Les réseaux fortement eutactiques, pp. 112-132 in Réseaux Euclidiens, Designs Sphériques et Formes Modulaires, ed. J. Martinet, L'Enseignement Mathématique, Geneva, 2001.

Crossrefs

Cf. A037075, A065535, A004026.

Sequence in context: A293606 A185376 A321484 * A351261 A191469 A091053

Adjacent sequences: A065533 A065534 A065535 * A065537 A065538 A065539

Keyword

nonn,nice,hard,more

Author

N. J. A. Sloane, Nov 16 2001

Extensions

It is known that a(6) >= 19, a(7) >= 10.

a(5) corrected and a(6) added from Batut & Martinet by Andrey Zabolotskiy, Feb 20 2021

Status

approved