# DMGT

ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

# IMPACT FACTOR 2018: 0.741

SCImago Journal Rank (SJR) 2018: 0.763

Rejection Rate (2018-2019): c. 84%

# Discussiones Mathematicae Graph Theory

## COMPETITION HYPERGRAPHS OF DIGRAPHS WITH CERTAIN PROPERTIES II HAMILTONICITY

 Martin Sonntag Faculty of Mathematics and Computer Science TU Bergakademie Freiberg Prüferstraße 1, D-09596 Freiberg, Germany e-mail: sonntag@mathe.tu-freiberg.de Hanns-Martin Teichert Institute of Mathematics University of Lübeck Wallstraß e 40, D-23560 Lübeck, Germany e-mail: teichert@math.uni-luebeck.de

## Abstract

If D = (V,A) is a digraph, its competition hypergraph C H(D) has vertex set V and e ⊆ V is an edge of C H(D) iff |e| ≥ 2 and there is a vertex v ∈ V, such that e = ND(v) = {w ∈ V|(w,v) ∈ A}. We give characterizations of C H(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 Fraughnaugh et al. [4] and Guichard [6].

Keywords: hypergraph, competition graph, hamiltonian digraph.

2000 Mathematics Subject Classification: 05C65, 05C20, 05C45.

## References

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