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arXiv · 2003.11406

On the $4$-rank of class groups of Dirichlet biquadratic fields

Étienne Fouvry·Peter Koymans·Carlo Pagano
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Abstract

We show that for $100\%$ of the odd, squarefree 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 $4$.

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Étienne Fouvry, Peter Koymans, Carlo Pagano. 2020-03-25. On the $4$-rank of class groups of Dirichlet biquadratic fields. https://arxiv.org/abs/2003.11406

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