%I M2215
%S 1,1,1,1,1,3,1,3,5,3,3,7,3,5,7,3,3,5,9,7,3,5,5,15,9,19,5,13,9,9,5,19,
%T 9,5,7,15,13,9,9,15,25,13,9,27,19,15,21,7,13,11,23,9,13,13,11,33,15,
%U 25,23,15,13
%N Class numbers of quadratic fields.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H D. Shanks, <a href="http://dx.doi.org/10.1090/S00255718197403520498">The simplest cubic fields</a>, Math. Comp., 28 (1974), 11371152.
%H <a href="/index/Qua#quadfield">Index entries for sequences related to quadratic fields</a>
%K nonn
%O 1,6
%A _N. J. A. Sloane_.
