{ "id": "2411.11103", "version": "v1", "published": "2024-11-17T15:49:12.000Z", "updated": "2024-11-17T15:49:12.000Z", "title": "Sums of S-units in X-coordinates of Pell equations", "authors": [ "Parvathi S Nair", "Sudhansu Sekhar Rout" ], "categories": [ "math.NT" ], "abstract": "Let $S$ be a fixed set of primes and let $(X_{l})_{l\\geq 1}$ be the $X$-coordinates of the positive integer solutions $(X, Y)$ of the Pell equation $X^2-dY^2 = 1$ corresponding to a non-square integer $d>1$. We show that there are only a finite number of non-square integers $d>1$ such that there are at least two different elements of the sequence $(X_{l})_{l\\geq 1}$ that can be represented as a sum of $S$-units with a fixed number of terms. Furthermore, we solve explicitly a particular case in which two of the $X$-coordinates are product of power of two and power of three.", "revisions": [ { "version": "v1", "updated": "2024-11-17T15:49:12.000Z" } ], "analyses": { "subjects": [ "11B37", "11D45", "11J86" ], "keywords": [ "pell equation", "non-square integer", "x-coordinates", "positive integer solutions", "finite number" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }