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%I M2263 #9 Jan 27 2014 08:57:35
%S 1,1,1,1,1,3,3,1,2,1,5,1,2,3,1,7,5,3,3,1,4,5,3,4,1,5,1,5,5,3,5,7,2,5,
%T 1,11,5,4,1,13,1,9,2,3,7,2,7,5,3,1,15,3,7,3,2,13,1,11,3,7,2,4,4,5,3,
%U 19,5,2,6,3,9,3,5,2,19,9,4,3,17,7,4,4,1,8,3,5,9,1,21,1,15,5,7,3,5,7,7,8,25
%N Number of classes per genus in quadratic field with discriminant -4n+1.
%D D. A. Buell, Binary Quadratic Forms. Springer-Verlag, NY, 1989, pp. 224-241.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%Y Cf. A003638.
%K nonn
%O 1,6
%A _N. J. A. Sloane_, _Mira Bernstein_