{ "id": "1406.6851", "version": "v1", "published": "2014-06-26T11:40:47.000Z", "updated": "2014-06-26T11:40:47.000Z", "title": "On Primitive Covering Numbers", "authors": [ "Lenny Jones", "Daniel White" ], "categories": [ "math.NT" ], "abstract": "In 2007, Zhi-Wei Sun defined a \\emph{covering number} to be a positive integer $L$ such that there exists a covering system of the integers where the moduli are distinct divisors of $L$ greater than 1. A covering number $L$ is called \\emph{primitive} if no proper divisor of $L$ is a covering number. Sun constructed an infinite set $\\mathcal L$ of primitive covering numbers, and he conjectured that every primitive covering number must satisfy a certain condition. In this paper, for a given $L\\in \\mathcal L$, we derive a formula that gives the exact number of coverings that have $L$ as the least common multiple of the set $M$ of moduli, under certain restrictions on $M$. Additionally, we disprove Sun's conjecture by constructing an infinite set of primitive covering numbers that do not satisfy his primitive covering number condition.", "revisions": [ { "version": "v1", "updated": "2014-06-26T11:40:47.000Z" } ], "analyses": { "keywords": [ "infinite set", "disprove suns conjecture", "primitive covering number condition", "distinct divisors", "proper divisor" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1406.6851J" } } }