{ "id": "1907.03145", "version": "v1", "published": "2019-07-06T15:57:16.000Z", "updated": "2019-07-06T15:57:16.000Z", "title": "On diagonal equations over finite fields via walks in NEPS of graphs", "authors": [ "Denis E. Videla" ], "comment": "8 pages", "categories": [ "math.CO", "math.NT" ], "abstract": "In this paper, we find a formula for the number of $r$-walks on NEPS of arbitrary graphs in any basis. We apply this formula to find the number of elements of a commutative ring that can be represented as a sum of $r$ units. We then also obtain the number of solutions $(x_i)_{i=1}^r$ with $x_i\\neq 0$ to the diagonal equation $x_{1}^k+\\cdots+x_{r}^k=b$ over a finite field $\\mathbb{F}_{p^m}$, obtaining an identity for generalized Jacobi sums.", "revisions": [ { "version": "v1", "updated": "2019-07-06T15:57:16.000Z" } ], "analyses": { "subjects": [ "05C25" ], "keywords": [ "finite field", "diagonal equation", "generalized jacobi sums", "arbitrary graphs" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }