{ "id": "1311.5252", "version": "v2", "published": "2013-11-20T22:34:03.000Z", "updated": "2015-08-04T21:20:34.000Z", "title": "On the $p$-integrality of $A$-hypergeometric series", "authors": [ "Alan Adolphson", "Steven Sperber" ], "comment": "Expanded introduction, Sections 2 and 5 rewritten, Section 7 added, small changes elsewhere", "categories": [ "math.NT", "math.AG" ], "abstract": "Let $A$ be a set of $N$ vectors in ${\\mathbb Z}^n$ and let $v$ be a vector in ${\\mathbb C}^N$ that has minimal negative support for $A$. Such a vector $v$ gives rise to a formal series solution of the $A$-hypergeometric system with parameter $\\beta = Av$. If $v$ lies in ${\\mathbb Q}^n$, then this series has rational coefficients. Let $p$ be a prime number. We characterize those $v$ whose coordinates are rational, $p$-integral, and lie in the closed interval $[-1,0]$ for which the corresponding normalized series solution has $p$-integral coefficients.", "revisions": [ { "version": "v1", "updated": "2013-11-20T22:34:03.000Z", "comment": "20 pages", "journal": null, "doi": null }, { "version": "v2", "updated": "2015-08-04T21:20:34.000Z" } ], "analyses": { "keywords": [ "hypergeometric series", "integrality", "formal series solution", "minimal negative support", "prime number" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1311.5252A" } } }