English

Diophantine tuples and Integral Ideals of $\mathbb{Q}(\sqrt{d})$

Number Theory 2025-09-09 v1 Combinatorics

Abstract

Suppose nn is the fundamental discriminant associated with a quadratic extension of Q\mathbb{Q}. We show that for every Diophantine mm-tuple {t1,t2,,tm} \{t_1, t_2, \ldots, t_m\} with the property D(n) D(n) , there exists integral ideals t1,t2,,tm \mathfrak{t}_1, \mathfrak{t}_2, \ldots, \mathfrak{t}_m of Q(n) \mathbb{Q}(\sqrt{n}) and c{1,2}c\in \{1,2\} such that ti=cN(ti) t_i= c\mathcal{N}(\mathfrak{t}_i) for i=1,2,,m i=1,2, \ldots, m . Here, N() \mathcal{N}(\cdot) denotes the norm map from Q(n)\mathbb{Q}(\sqrt{n}) to Q\mathbb{Q}. Moreover, we explicitly construct the above ideals for Diophantine pairs {a1,a2}\{a_1, a_2\} whenever gcd(a1,a2)=1\gcd(a_1, a_2) = 1.

Keywords

Cite

@article{arxiv.2509.06522,
  title  = {Diophantine tuples and Integral Ideals of $\mathbb{Q}(\sqrt{d})$},
  author = {Kalyan Chakraborty and Shubham Gupta and Krishnarjun Krishnamoorthy},
  journal= {arXiv preprint arXiv:2509.06522},
  year   = {2025}
}

Comments

7 pages. Comments and suggestions welcome