A005134 Number of n-dimensional unimodular lattice (or quadratic forms). (Formerly M0219)

1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 5, 8, 9, 13, 16, 28, 40, 68, 117, 297, 665

Offset

0,9

References

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 49.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=0..25.

Crossrefs

Cf. A054907-A054909, A054911.

Sequence in context: A153683 A275882 A005139 * A081651 A269333 A029193

Adjacent sequences: A005131 A005132 A005133 * A005135 A005136 A005137

Keyword

nonn,nice,hard

Author

N. J. A. Sloane

Status

approved