English

The Diophantine equation $f(x)=g(y)$ for polynomials with simple rational roots

Number Theory 2022-04-27 v1

Abstract

In this paper we consider Diophantine equations of the form f(x)=g(y)f(x)=g(y) where ff has simple rational roots and gg has rational coefficients. We give strict conditions for the cases where the equation has infinitely many solutions in rationals with a bounded denominator. We give examples illustrating that the given conditions are necessary. It turns out that such equations with infinitely many solutions are strongly related to Prouhet-Tarry-Escott tuples. In the special, but important case when gg has only simple rational roots as well, we can give a simpler statement. Also we provide an application to equal products with terms belonging to blocks of consecutive integers of bounded length. The latter theorem is related to problems and results of Erd\H{o}s and Turk, and of Erd\H{o}s and Graham.

Keywords

Cite

@article{arxiv.2204.12345,
  title  = {The Diophantine equation $f(x)=g(y)$ for polynomials with simple rational roots},
  author = {L. Hajdu and R. Tijdeman},
  journal= {arXiv preprint arXiv:2204.12345},
  year   = {2022}
}