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%I #11 Mar 31 2012 08:51:45
%S 1,39,47,108,37,40,4,3
%N The number of totally real number fields of degree n with definite Eichler orders <=2.
%C By the Odlyzko bounds, there are only finitely many such fields and they have been explicitly enumerated (by Voight) and no field satisfying the bound with n => 9, for a total of 279 fields. Kirschmer and Voight (pp. 26-27) also enumerate the ideal classes explicitly, Abstract: We provide algorithms to count and enumerate representatives of the (right) ideal classes of an Eichler order in a quaternion algebra defined over a number field. We analyze the run time of these algorithms and consider several related problems, including the computation of two-sided ideal classes, isomorphism classes of orders, connecting ideals for orders and ideal principalization. We conclude by giving the complete list of definite Eichler orders with class number at most 2.
%H Markus Kirschmer and John Voight, <a href="http://arxiv.org/abs/0808.3833">Algorithmic enumeration of ideal classes for quaternion orders</a>, arXiv:0808.3833 [math.NT]
%H John Voight, <a href="http://arxiv.org/abs/0802.0194">Enumeration of totally real number fields of bounded root discriminant</a>, Algorithmic number theory, eds. Alfred van der Poorten and Andreas Stein, Lecture notes in computer science, vol. 5011, Springer, Berlin, 2008, 268-281.
%K nonn,fini,full
%O 1,2
%A _Jonathan Vos Post_, Aug 30 2008