Domination hypergraphs of certain digraphs
نویسندگان
چکیده
منابع مشابه
Competition hypergraphs of digraphs with certain properties I. Strong connectedness
If D = (V,A) is a digraph, its competition hypergraph CH(D) has the vertex set V and e ⊆ V is an edge of CH(D) iff |e| ≥ 2 and there is a vertex v ∈ V , such that e = {w ∈ V |(w, v) ∈ A}. We tackle the problem to minimize the number of strong components in D without changing the competition hypergraph CH(D). The results are closely related to the corresponding investigations for competition gra...
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If D = (V,A) is a digraph, its competition hypergraph CH(D) has vertex set V and e ⊆ V is an edge of CH(D) iff |e| ≥ 2 and there is a vertex v ∈ V , such that e = N− D (v) = {w ∈ V |(w, v) ∈ A}. We give characterizations of CH(D) in case of hamiltonian digraphs D and, more general, of digraphs D having a τ -cycle factor. The results are closely related to the corresponding investigations for co...
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ژورنال
عنوان ژورنال: Opuscula Mathematica
سال: 2010
ISSN: 1232-9274
DOI: 10.7494/opmath.2010.30.2.179