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arXiv · 1609.02292

The mean number of 3-torsion elements in ray class groups of quadratic fields

Ila Varma
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Abstract

We determine the average number of $3$-torsion elements in the ray class groups of fixed (integral) conductor $c$ of quadratic fields ordered by absolute discriminant, generalizing Davenport and Heilbronn's theorem on class groups. A consequence of this result is that a positive proportion of such ray class groups of quadratic fields have trivial 3-torsion subgroup whenever the conductor $c$ is taken to be a squarefree integer having very few prime factors none of which are congruent to $1 \bmod 3$. Additionally, we compute the second main term for the number of $3$-torsion elements in ray class groups with fixed conductor of quadratic fields with bounded discriminant.

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Ila Varma. 2016-09-08. The mean number of 3-torsion elements in ray class groups of quadratic fields. https://arxiv.org/abs/1609.02292

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