English

A Polynomial Variant of Diophantine Triples in Linear Recurrences

Number Theory 2023-04-12 v1

Abstract

Let (Gn)n=0 (G_n)_{n=0}^{\infty} be a polynomial power sum, i.e. a simple linear recurrence sequence of complex polynomials with power sum representation Gn=f1α1n++fkαkn G_n = f_1\alpha_1^n + \cdots + f_k\alpha_k^n and polynomial characteristic roots α1,,αk \alpha_1,\ldots,\alpha_k . For a fixed polynomial p p , we consider triples (a,b,c) (a,b,c) of pairwise distinct non-zero polynomials such that ab+p,ac+p,bc+p ab+p, ac+p, bc+p are elements of (Gn)n=0 (G_n)_{n=0}^{\infty} . We will prove that under a suitable dominant root condition there are only finitely many such triples if neither f1 f_1 nor f1α1 f_1 \alpha_1 is a perfect square.

Keywords

Cite

@article{arxiv.2006.12173,
  title  = {A Polynomial Variant of Diophantine Triples in Linear Recurrences},
  author = {Clemens Fuchs and Sebastian Heintze},
  journal= {arXiv preprint arXiv:2006.12173},
  year   = {2023}
}

Comments

9 pages