{ "id": "2310.16701", "version": "v1", "published": "2023-10-25T15:18:36.000Z", "updated": "2023-10-25T15:18:36.000Z", "title": "Odd-Sunflowers", "authors": [ "Peter Frankl", "János Pach", "Dömötör Pálvölgyi" ], "categories": [ "math.CO" ], "abstract": "Extending the notion of sunflowers, we call a family of at least two sets an odd-sunflower if every element of the underlying set is contained in an odd number of sets or in none of them. It follows from the Erd\\H os--Szemer\\'edi conjecture, recently proved by Naslund and Sawin, that there is a constant $\\mu<2$ such that every family of subsets of an $n$-element set that contains no odd-sunflower consists of at most $\\mu^n$ sets. We construct such families of size at least $1.5021^n$. We also characterize minimal odd-sunflowers of triples.", "revisions": [ { "version": "v1", "updated": "2023-10-25T15:18:36.000Z" } ], "analyses": { "keywords": [ "odd number", "os-szemeredi conjecture", "element set", "odd-sunflower consists", "characterize minimal odd-sunflowers" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }