Competition hypergraphs of digraphs with certain properties II. Hamiltonicity
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 = 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 competition graphs in K.F.Fraughnaugh et al., Competition graphs of strongly connected and hamiltonian digraphs; SIAM J. Discr. Math. 8 (1995), 179-185 and D.R. Guichard, Competition graphs of hamiltonian digraphs; SIAM J. Discr. Math. 11 (1998), 128–134.
منابع مشابه
Niche hypergraphs
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:
- Discussiones Mathematicae Graph Theory
دوره 28 شماره
صفحات -
تاریخ انتشار 2008