Competition Hypergraphs of Products of Digraphs
نویسندگان
چکیده
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 = {w ∈ V |(w, v) ∈ A}. For several products D1 ◦D2 of digraphs D1 and D2, we investigate the relations between the competition hypergraphs of the factors D1, D2 and the competition hypergraph of their product D1 ◦D2.
منابع مشابه
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If D = (V,A) is a digraph, its niche hypergraph NH(D) = (V, E) has the edge set E = {e ⊆ V | |e| ≥ 2 ∧ ∃v ∈ V : e = N− D (v) ∨ e = N + D (v)}. Niche hypergraphs generalize the well-known niche graphs (cf. [?]) and are closely related to competition hypergraphs (cf. [?]) as well as double competition hypergraphs (cf. [?]). We present several properties of niche hypergraphs of acyclic digraphs.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 25 شماره
صفحات -
تاریخ انتشار 2009