{ "id": "2408.15174", "version": "v1", "published": "2024-08-27T16:11:41.000Z", "updated": "2024-08-27T16:11:41.000Z", "title": "On Lev's periodicity conjecture", "authors": [ "Christian Reiher" ], "categories": [ "math.CO", "math.NT" ], "abstract": "We classify the sum-free subsets of ${\\mathbb F}_3^n$ whose density exceeds $\\frac16$. This yields a resolution of Vsevolod Lev's periodicity conjecture, which asserts that if a sum-free subset ${A\\subseteq {\\mathbb F}_3^n}$ is maximal with respect to inclusion and aperiodic (in the sense that there is no non-zero vector $v$ satisfying $A+v=A$), then $|A|\\le \\frac12(3^{n-1}+1)$ -- a bound known to be optimal if $n\\ne 2$, while for $n=2$ there are no such sets.", "revisions": [ { "version": "v1", "updated": "2024-08-27T16:11:41.000Z" } ], "analyses": { "subjects": [ "11B13", "11B30", "11P70" ], "keywords": [ "sum-free subset", "vsevolod levs periodicity conjecture", "density exceeds", "non-zero vector", "resolution" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }