{ "id": "1807.01181", "version": "v1", "published": "2018-07-02T15:36:05.000Z", "updated": "2018-07-02T15:36:05.000Z", "title": "On sums and products in a field", "authors": [ "Guang-Liang Zhou", "Zhi-Wei Sun" ], "comment": "7 pages", "categories": [ "math.NT" ], "abstract": "In this paper we study sums and products in a field. Let $F$ be a field with ${\\rm ch}(F)\\not=2$, where ${\\rm ch}(F)$ is the characteristic of $F$. For any integer $k\\ge4$, we show that each $x\\in F$ can be written as $a_1+\\ldots+a_k$ with $a_1,\\ldots,a_k\\in F$ and $a_1\\ldots a_k=1$ if ${\\rm ch}(F)\\not=3$, and that for any $\\alpha\\in F\\setminus\\{0\\}$ we can write each $x\\in F$ as $a_1\\ldots a_k$ with $a_1,\\ldots,a_k\\in F$ and $a_1+\\ldots+a_k=\\alpha$. We also prove that for any $x\\in F$ and $k\\in\\{2,3,\\ldots\\}$ there are $a_1,\\ldots,a_{2k}\\in F$ such that $a_1+\\ldots+a_{2k}=x=a_1\\ldots a_{2k}$.", "revisions": [ { "version": "v1", "updated": "2018-07-02T15:36:05.000Z" } ], "analyses": { "subjects": [ "11D85", "11P99", "11T99" ], "keywords": [ "study sums", "characteristic" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }