A096445 Number of reduced primitive positive definite binary quadratic forms of determinant n^2.

1, 1, 2, 2, 2, 4, 4

Offset

1,3

Comments

Equivalently, of discriminant -4n^2.

Links

Table of n, a(n) for n=1..7.

J. H. Conway and N. J. A. Sloane, Sphere Packings, Lattices and Groups, Springer-Verlag, 3rd edition, 1999, see Table 15.1.

Crossrefs

Equals A096446(n^2). Cf. A006374.

Sequence in context: A228660 A228796 A155837 * A125915 A071472 A367120

Adjacent sequences: A096442 A096443 A096444 * A096446 A096447 A096448

Keyword

nonn,more

Author

N. J. A. Sloane, Aug 11 2004

Status

approved