English

Doubly regular Diophantine quadruples

Number Theory 2020-10-12 v2

Abstract

For a nonzero integer n, a set of m distinct nonzero integers {a_1,a_2,...,a_m} such that a_i a_j + n is a perfect square for all 1 <= i < j <= m, is called a D(n)-m-tuple. In this paper, by using properties of so-called regular Diophantine m-tuples and certain family of elliptic curves, we show that there are infinitely many essentially different sets consisting of perfect squares which are simultaneously D(n_1)-quadruples and D(n_2)-quadruples with distinct non-zero squares n_1 and n_2.

Keywords

Cite

@article{arxiv.2001.10702,
  title  = {Doubly regular Diophantine quadruples},
  author = {Andrej Dujella and Vinko Petričević},
  journal= {arXiv preprint arXiv:2001.10702},
  year   = {2020}
}

Comments

7 pages, revised version, to appear in Rev. R. Acad. Cienc. Exactas Fis. Nat. Ser. A Math. RACSAM

R2 v1 2026-06-23T13:23:41.079Z