Results 11 to 20 of about 118 (93)
Sum-List Colouring of Unions of a Hypercycle and a Path with at Most Two Vertices in Common
Discussiones Mathematicae Graph Theory, 2020 Given a hypergraph and a function f : V () → , we say that is f-choosable if there is a proper vertex colouring ϕ of such that ϕ (v) ∈ L(v) for all v ∈ V (), where L : V () → 2 is any assignment of f(v) colours to a vertex v.
Drgas-Burchardt Ewa +1 more
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The (1, 2)-step competition graph of a hypertournament
Open Mathematics, 2021 In 2011, Factor and Merz [Discrete Appl. Math. 159 (2011), 100–103] defined the (1,2)\left(1,2)-step competition graph of a digraph. Given a digraph D=(V,A)D=\left(V,A), the (1,2)\left(1,2)-step competition graph of D, denoted C1,2(D){C}_{1,2}\left(D ...
Li Ruijuan, An Xiaoting, Zhang Xinhong
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On the α-Spectral Radius of Uniform Hypergraphs
Discussiones Mathematicae Graph Theory, 2020 For 0 ≤ α ---lt--- 1 and a uniform hypergraph G, the α-spectral radius of G is the largest H-eigenvalue of αD(G)+(1−α)A(G), where D(G) and A(G) are the diagonal tensor of degrees and the adjacency tensor of G, respectively. We give upper bounds for the α-
Guo Haiyan, Zhou Bo
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Compression with wildcards: All exact or all minimal hitting sets
Open Mathematics, 2023 Our objective is the compressed enumeration (based on wildcards) of all minimal hitting sets of general hypergraphs. To the author’s best knowledge, the only previous attempt towards compression, due to Toda, is based on binary decision diagrams and much
Wild Marcel
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, 2010 We investigate a family of polytopes introduced by E.M. Feichtner, A. Postnikov and B. Sturmfels, which were named nestohedra. The vertices of these polytopes may intuitively be understood as constructions of hypergraphs.
K. Dosen, Z. Petric
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Cyclic Partitions of Complete and Almost Complete Uniform Hypergraphs
Discussiones Mathematicae Graph Theory, 2022 We consider cyclic partitions of the complete k-uniform hypergraph on a finite set V, minus a set of s edges, s ≥ 0. An s-almost t-complementary k-hypergraph is a k-uniform hypergraph with vertex set V and edge set E for which there exists a permutation ...
Dilbarjot, Gosselin Shonda Dueck
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The Lagrangian Density of {123, 234, 456} and the Turán Number of its Extension
Discussiones Mathematicae Graph Theory, 2021 Given a positive integer n and an r-uniform hypergraph F, the Turán number ex(n, F ) is the maximum number of edges in an F -free r-uniform hypergraph on n vertices.
Chen Pingge, Liang Jinhua, Peng Yuejian
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Asymptotic Enumeration of Non-Uniform Linear Hypergraphs
Discussiones Mathematicae Graph Theory, 2022 A linear hypergraph, also known as a partial Steiner system, is a collection of subsets of a set such that no two of the subsets have more than one element in common.
Hasheminezhad Mahdieh, McKay Brendan D.
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Niche Hypergraphs of Products of Digraphs
Discussiones Mathematicae Graph Theory, 2020 If D = (V, A) is a digraph, its niche hypergraph Nℋ(D) = (V, ℰ) has the edge set ℰ={e⊆V||e|≥2∧∃ υ∈V:e=ND−(υ)∨e=ND+(υ)}{\cal E} = \{ {e \subseteq V| | e | \ge 2 \wedge \exists \, \upsilon \in V:e = N_D^ - ( \upsilon ) \vee e = N_D^ + ( \upsilon ...
Sonntag Martin, Teichert Hanns-Martin
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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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