{ "id": "2209.15493", "version": "v1", "published": "2022-09-30T14:29:41.000Z", "updated": "2022-09-30T14:29:41.000Z", "title": "Rainbow triangles in families of triangles", "authors": [ "Ido Goorevitch", "Ron Holzman" ], "comment": "6 pages, 5 figures", "categories": [ "math.CO" ], "abstract": "We prove that a family $\\mathcal{T}$ of distinct triangles on $n$ given vertices that does not have a rainbow triangle (that is, three edges, each taken from a different triangle in $\\mathcal{T}$, that form together a triangle) must be of size at most $\\frac{n^2}{8}$. We also show that this result is sharp and characterize the extremal case. In addition, we discuss a version of this problem in which the triangles are not necessarily distinct, and show that in this case, the same bound holds asymptotically.", "revisions": [ { "version": "v1", "updated": "2022-09-30T14:29:41.000Z" } ], "analyses": { "subjects": [ "05C35" ], "keywords": [ "rainbow triangle", "distinct triangles", "extremal case", "bound holds", "necessarily distinct" ], "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable" } } }