A096446 Number of reduced primitive positive definite binary quadratic forms of determinant n.

1, 1, 2, 1, 2, 2, 2, 3, 2, 2, 4, 2

Offset

1,3

Comments

Equivalently, of discriminant -4n.

Links

Table of n, a(n) for n=1..12.

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

Crossrefs

A096445(n) = a(n^2). A006374 gives the number if imprimitive forms are also included.

Sequence in context: A299484 A327007 A336767 * A274701 A184956 A340134

Adjacent sequences: A096443 A096444 A096445 * A096447 A096448 A096449

Keyword

nonn,more

Author

N. J. A. Sloane, Aug 11 2004

Status

approved