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A006371 Number of reduced binary quadratic forms of discriminant -n.
(Formerly M0207)
2

%I M0207

%S 1,1,1,1,1,2,2,2,1,2,3,2,2,2,3,3,2,3,4,2,1,4,5,4,2,2,4,4,3,4,5,4,1,4,

%T 7,3,3,4,5,6,3,4,6,2,2,6,8,6,3,3,5,6,3,6,8,4,2,6,10,4,2,6,5,7,5,4,8,4,

%U 3,8,10,8,3,2,7,6,4,8,10,6,1,8

%N Number of reduced binary quadratic forms of discriminant -n.

%D H. Davenport, The Higher Arithmetic. Cambridge Univ. Press, 5th edition, 1982, p. 144.

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

%H Rick L. Shepherd, <a href="http://libres.uncg.edu/ir/uncg/f/Shepherd_uncg_0154M_11099.pdf">Binary quadratic forms and genus theory</a>, Master of Arts Thesis, University of North Carolina at Greensboro, 2013.

%Y Cf. A006374.

%K nonn

%O 3,6

%A _N. J. A. Sloane_

%E More terms from _Sean A. Irvine_, Mar 19 2017

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Last modified May 31 19:11 EDT 2020. Contains 334748 sequences. (Running on oeis4.)