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ON THE $4$-RANK OF CLASS GROUPS OF DIRICHLET BIQUADRATIC FIELDS

Published online by Cambridge University Press:  22 December 2020

Étienne Fouvry
Affiliation:
Université Paris–Saclay, CNRS, Laboratoire de mathématiques d’Orsay, 91405Orsay, France (Etienne.Fouvry@universite-paris-saclay.fr)
Peter Koymans
Affiliation:
Max Planck Institute for Mathematics, Vivatsgasse 7, 53111Bonn, Germany (koymans@mpim-bonn.mpg.de)
Carlo Pagano
Affiliation:
Max Planck Institute for Mathematics, Vivatsgasse 7, 53111Bonn, Germany (carlein90@gmail.com)

Abstract

We show that for $100\%$ of the odd, square free integers $n> 0$ , the $4$ -rank of $\text {Cl}(\mathbb{Q} (i, \sqrt {n}))$ is equal to $\omega _3(n) - 1$ , where $\omega _3$ is the number of prime divisors of n that are $3$ modulo $4$ .

Type
Research Article
Copyright
© The Author(s), 2020. Published by Cambridge University Press

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