$p$-adic quotient sets: Cubic forms

Deepa Antony; Rupam Barman

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arXiv · 2110.05420

$p$-adic quotient sets: Cubic forms

Deepa Antony·Rupam Barman

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Abstract

For $A\subseteq \{1, 2, \ldots\}$, we consider $R(A)=\{a/b: a, b\in A\}$. It is an open problem to study the denseness of $R(A)$ in the $p$-adic numbers when $A$ is the set of nonzero values assumed by a cubic form. We study this problem for the cubic forms $ax^3+by^3$, where $a$ and $b$ are integers. We also prove that if $A$ is the set of nonzero values assumed by a non-degenerate, integral and primitive cubic form with more than 9 variables, then $R(A)$ is dense in $\mathbb{Q}_p$.

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Deepa Antony, Rupam Barman. 2021-10-11. $p$-adic quotient sets: Cubic forms. https://arxiv.org/abs/2110.05420

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