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A096446 Number of reduced primitive positive definite binary quadratic forms of determinant n. 2
1, 1, 2, 1, 2, 2, 2, 3, 2, 2, 4, 2 (list; graph; refs; listen; history; text; internal format)
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: A192394 A085033 A230254 * A184956 A218469 A230502

Adjacent sequences:  A096443 A096444 A096445 * A096447 A096448 A096449

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Aug 11 2004

STATUS

approved

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Last modified November 21 19:17 EST 2014. Contains 249784 sequences.