{ "id": "2310.13190", "version": "v1", "published": "2023-10-19T22:59:43.000Z", "updated": "2023-10-19T22:59:43.000Z", "title": "A hypergraph analog of Dirac's Theorem for long cycles in 2-connected graphs, II: Large uniformities", "authors": [ "Alexandr Kostochka", "Ruth Luo", "Grace McCourt" ], "comment": "23 pages, 1 figure. arXiv admin note: text overlap with arXiv:2212.14516", "categories": [ "math.CO" ], "abstract": "Dirac proved that each $n$-vertex $2$-connected graph with minimum degree $k$ contains a cycle of length at least $\\min\\{2k, n\\}$. We obtain analogous results for Berge cycles in hypergraphs. Recently, the authors proved an exact lower bound on the minimum degree ensuring a Berge cycle of length at least $\\min\\{2k, n\\}$ in $n$-vertex $r$-uniform $2$-connected hypergraphs when $k \\geq r+2$. In this paper we address the case $k \\leq r+1$ in which the bounds have a different behavior. We prove that each $n$-vertex $r$-uniform $2$-connected hypergraph $H$ with minimum degree $k$ contains a Berge cycle of length at least $\\min\\{2k,n,|E(H)|\\}$. If $|E(H)|\\geq n$, this bound coincides with the bound of the Dirac's Theorem for 2-connected graphs.", "revisions": [ { "version": "v1", "updated": "2023-10-19T22:59:43.000Z" } ], "analyses": { "subjects": [ "05D05", "05C65", "05C38", "05C35" ], "keywords": [ "diracs theorem", "hypergraph analog", "long cycles", "large uniformities", "berge cycle" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }