Results 21 to 30 of about 81 (80)
High Girth Hypergraphs with Unavoidable Monochromatic or Rainbow Edges
Discussiones Mathematicae Graph Theory, 2022 A classical result of Erdős and Hajnal claims that for any integers k, r, g ≥ 2 there is an r-uniform hypergraph of girth at least g with chromatic number at least k.
Axenovich Maria, Karrer Annette
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Rainbow spanning structures in graph and hypergraph systems
Forum of Mathematics, Sigma, 2023 We study the following rainbow version of subgraph containment problems in a family of (hyper)graphs, which generalizes the classical subgraph containment problems in a single host graph. For a collection $\mathit {\mathbf {G}}=\{G_1, G_2,\ldots , G_{
Yangyang Cheng +3 more
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The complexity of recognizing $ABAB$-free hypergraphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceThe study of geometric hypergraphs gave rise to the notion of $ABAB$-free hypergraphs. A hypergraph $\mathcal{H}$ is called $ABAB$-free if there is an ordering of its vertices such that there are no hyperedges $A,B$ and vertices $v_1,v_2,v_3,v_4$ in this
Gábor Damásdi +3 more
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ℤ2 × ℤ2-Cordial Cycle-Free Hypergraphs
Discussiones Mathematicae Graph Theory, 2021 Hovey introduced A-cordial labelings as a generalization of cordial and harmonious labelings [7]. If A is an Abelian group, then a labeling f : V (G) → A of the vertices of some graph G induces an edge labeling on G; the edge uv receives the label f(u) +
Cichacz Sylwia +2 more
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Constructing Regular Self-complementary Uniform Hypergraphs [PDF]
, 2011 AMS Subject Classication Codes: 05C65, 05B05 05E20, 05C85.In this paper, we examine the possible orders of t-subset-regular self-complementary k-uniform hypergraphs, which form examples of large sets of two isomorphic t-designs.
Gosselin, Shonda, Shonda Gosselin
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Elimination Properties for Minimal Dominating Sets of Graphs
Discussiones Mathematicae Graph Theory, 2023 A dominating set of a graph is a vertex subset such that every vertex not in the subset is adjacent to at least one in the subset. In this paper we study whenever there exists a new dominating set contained (respectively, containing) the subset obtained ...
Martí-Farré Jaume +3 more
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Discussiones Mathematicae Graph Theory, 2023 Let ℓ be a positive integer, k = 2ℓ or k = 2ℓ + 1, and let n be a positive integer with n ≡ 1 (mod 2ℓ+1). For a prime p, n(p) denotes the largest integer i such that pi divides n.
Lesniak Linda +2 more
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On the Sizes of (k, l)-Edge-Maximal r-Uniform Hypergraphs
Discussiones Mathematicae Graph Theory, 2023 Let H = (V, E) be a hypergraph, where V is a set of vertices and E is a set of non-empty subsets of V called edges. If all edges of H have the same cardinality r, then H is an r-uniform hypergraph; if E consists of all r-subsets of V, then H is a ...
Tian Yingzhi +3 more
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Tower Gaps in Multicolour Ramsey Numbers
Forum of Mathematics, Sigma, 2023 Resolving a problem of Conlon, Fox and Rödl, we construct a family of hypergraphs with arbitrarily large tower height separation between their $2$ -colour and q-colour Ramsey numbers.
Quentin Dubroff +3 more
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Revisiting hypergraph models for sparse matrix partitioning [PDF]
, 2006 . We provide an exposition of hypergraph models for parallelizing sparse matrix-vector multiplies. Our aim is to emphasize the expressive power of hypergraph models.
Uçar, Bora +4 more
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