{ "id": "math/0505128", "version": "v9", "published": "2005-05-09T15:54:48.000Z", "updated": "2007-03-08T14:26:35.000Z", "title": "Mixed sums of squares and triangular numbers", "authors": [ "Zhi-Wei Sun" ], "comment": "11 pages", "journal": "Acta Arith. 127(2007), no.2, 103-113", "categories": [ "math.NT", "math.CO" ], "abstract": "By means of $q$-series, we prove that any natural number is a sum of an even square and two triangular numbers, and that each positive integer is a sum of a triangular number plus $x^2+y^2$ for some integers $x$ and $y$ with $x\\not\\equiv y (mod 2)$ or $x=y>0$. The paper also contains some other results and open conjectures on mixed sums of squares and triangular numbers.", "revisions": [ { "version": "v9", "updated": "2007-03-08T14:26:35.000Z" } ], "analyses": { "subjects": [ "11E25", "05A30", "11B65", "11D85", "11P99" ], "keywords": [ "mixed sums", "triangular number plus", "natural number", "open conjectures", "positive integer" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......5128S" } } }