1,2

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.

J. Martinet and B. Venkov, Les reseaux fortement eutactiques, pp. 112-132 in Reseaux Euclidiens, Designs Spheriques et Formes Modulaires, ed. J. Martinet, L'Enseignement Mathematiques, Geneva, 2001.

Cf. A037075, A065535, A004026.

Sequence in context: A159069 A162681 A070301 this_sequence A088414 A133441 A086254

Adjacent sequences: A065533 A065534 A065535 this_sequence A065537 A065538 A065539

nonn,nice,hard

N. J. A. Sloane (njas(AT)research.att.com), Nov 16 2001

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