{ "id": "2008.10294", "version": "v1", "published": "2020-08-24T09:54:01.000Z", "updated": "2020-08-24T09:54:01.000Z", "title": "Nontrivial effective lower bounds for the least common multiple of a $q$-arithmetic progression", "authors": [ "Bakir Farhi" ], "comment": "15 pages", "categories": [ "math.NT" ], "abstract": "This paper is devoted to establish nontrivial effective lower bounds for the least common multiple of consecutive terms of a sequence ${(u_n)}_{n \\in \\mathbb{N}}$ whose general term has the form $u_n = r {[n]}_q + u_0$, where $q , r$ are positive integers and $u_0$ is a non-negative integer such that $\\mathrm{gcd}(u_0 , r) = \\mathrm{gcd}(u_1 , q) = 1$. For such a sequence, we show that for all positive integer $n$, we have $\\mathrm{lcm}\\{u_1 , u_2 , \\dots , u_n\\} \\geq c_1 \\cdot c_2^n \\cdot q^{\\frac{n^2}{4}}$, where $c_1$ and $c_2$ are positive constants depending only on $q , r$ and $u_0$. This can be considered as a $q$-analog of the lower bounds already obtained by the author (in 2005) and by Hong and Feng (in 2006) for the arithmetic progressions.", "revisions": [ { "version": "v1", "updated": "2020-08-24T09:54:01.000Z" } ], "analyses": { "subjects": [ "11A05", "11B25", "11B65", "05A30" ], "keywords": [ "arithmetic progression", "common multiple", "positive integer", "establish nontrivial effective lower bounds", "general term" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }