{ "id": "2202.09219", "version": "v1", "published": "2022-02-18T14:37:37.000Z", "updated": "2022-02-18T14:37:37.000Z", "title": "$\\mathbb{Q}$-curves and the Lebesgue-Nagell equation", "authors": [ "Michael A. Bennett", "Philippe Michaud-Jacobs", "Samir Siksek" ], "comment": "13 pages", "categories": [ "math.NT" ], "abstract": "In this paper, we consider the equation \\[ x^2 - q^{2k+1} = y^n, \\qquad q \\nmid x, \\quad 2 \\mid y, \\] for integers $x,q,k,y$ and $n$, with $k \\geq 0$ and $n \\geq 3$. We extend work of the first and third-named authors by finding all solutions in the cases $q= 41$ and $q = 97$. We do this by constructing a Frey-Hellegouarch $\\mathbb{Q}$-curve defined over the real quadratic field $K=\\mathbb{Q}(\\sqrt{q})$, and using the modular method with multi-Frey techniques.", "revisions": [ { "version": "v1", "updated": "2022-02-18T14:37:37.000Z" } ], "analyses": { "subjects": [ "11D41", "11D61", "11F80", "11G05" ], "keywords": [ "lebesgue-nagell equation", "real quadratic field", "extend work", "modular method", "multi-frey techniques" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }