A096445 - OEIS

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A096445

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

%I #4 Oct 04 2012 10:28:52

%S 1,1,2,2,2,4,4

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

%C Equivalently, of discriminant -4n^2.

%H J. H. Conway and N. J. A. Sloane, <a href="http://neilsloane.com/doc/splag.html">Sphere Packings, Lattices and Groups</a>, Springer-Verlag, 3rd edition, 1999, see Table 15.1.

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

%K nonn,more

%O 1,3

%A _N. J. A. Sloane_, Aug 11 2004