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arXiv · 2608.10335

On the Squarefree Values of Degree-$2q$ Polynomials

Sergio Ricardo Zapata Ceballos·Fatemeh Jalalvand
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Abstract

In this work, we show that if $h(x)$ is an irreducible monic integer polynomial of degree $2q$ (with $q$ prime), whose defining field extension of $\mathbb{Q}$ contains a Galois extension of degree $q$, then there is a positive density of integers $n$ such that $h(n)$ is squarefree; in particular, $h(n)$ is squarefree for infinitely many integers $n$. As an application, we prove that the family of exceptional cubic fields contains an infinite subfamily whose unit shapes converge to the hexagonal lattice. To the best of our knowledge, this is the first example of a family of non-Galois totally real cubic fields whose unit shapes converge to the hexagonal lattice.

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Sergio Ricardo Zapata Ceballos, Fatemeh Jalalvand. 2026-08-11. On the Squarefree Values of Degree-$2q$ Polynomials. https://arxiv.org/abs/2608.10335

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