{ "id": "1407.4845", "version": "v1", "published": "2014-07-17T21:24:17.000Z", "updated": "2014-07-17T21:24:17.000Z", "title": "Hamiltonicity and $σ$-hypergraphs", "authors": [ "Christina Zarb" ], "categories": [ "math.CO" ], "abstract": "We define and study a special type of hypergraph. A $\\sigma$-hypergraph $H= H(n,r,q$ $\\mid$ $\\sigma$), where $\\sigma$ is a partition of $r$, is an $r$-uniform hypergraph having $nq$ vertices partitioned into $ n$ classes of $q$ vertices each. If the classes are denoted by $V_1$, $V_2$,...,$V_n$, then a subset $K$ of $V(H)$ of size $r$ is an edge if the partition of $r$ formed by the non-zero cardinalities $ \\mid$ $K$ $\\cap$ $V_i \\mid$, $ 1 \\leq i \\leq n$, is $\\sigma$. The non-empty intersections $K$ $\\cap$ $V_i$ are called the parts of $K$, and $s(\\sigma)$ denotes the number of parts. We consider various types of cycles in hypergraphs such as Berge cycles and sharp cycles in which only consecutive edges have a nonempty intersection. We show that most $\\sigma$-hypergraphs contain a Hamiltonian Berge cycle and that, for $n \\geq s+1$ and $q \\geq r(r-1)$, a $\\sigma$-hypergraph $H$ always contains a sharp Hamiltonian cycle. We also extend this result to $k$-intersecting cycles.", "revisions": [ { "version": "v1", "updated": "2014-07-17T21:24:17.000Z" } ], "analyses": { "subjects": [ "05C65", "05C45" ], "keywords": [ "hamiltonicity", "hamiltonian berge cycle", "sharp hamiltonian cycle", "non-zero cardinalities", "non-empty intersections" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1407.4845Z" } } }