ArticleOriginal scientific text
Title
Competition hypergraphs of digraphs with certain properties I. Strong connectedness
Authors 1, 2
Affiliations
- Faculty of Mathematics and Computer Science, TU Bergakademie Freiberg, Prüferstraße 1, D-09596 Freiberg, Germany
- Institute of Mathematics, University of Lübeck, Wallstraß e 40, D-23560 Lübeck, Germany
Abstract
If D = (V,A) is a digraph, its competition hypergraph (D) has the vertex set V and e ⊆ V is an edge of (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 (D). The results are closely related to the corresponding investigations for competition graphs in Fraughnaugh et al. [3].
Keywords
hypergraph, competition graph, strong component
Bibliography
- J. Bang-Jensen and G. Gutin, Digraphs: theory, algorithms and applications (Springer, London, 2001).
- J.E. Cohen, Interval graphs and food webs: a finding and a problem (Rand Corporation Document 17696-PR, Santa Monica, CA, 1968).
- K.F. Fraughnaugh, J.R. Lundgren, S.K. Merz, J.S. Maybee and N.J. Pullman, Competition graphs of strongly connected and hamiltonian digraphs, SIAM J. Discrete Math. 8 (1995) 179-185, doi: 10.1137/S0895480191197234.
- S.R. Kim, The competition number and its variants, in: J. Gimbel, J.W. Kennedy and L.V. Quintas (eds.), Quo vadis, graph theory?, Ann. of Discrete Math. 55 (1993) 313-326.
- J.R. Lundgren, Food webs, competition graphs, competition-common enemy graphs and niche graphs, in: F. Roberts (ed.), Applications of combinatorics and graph theory to the biological and social sciences, IMA 17 (Springer, New York, 1989) 221-243.
- F.S. Roberts, Competition graphs and phylogeny graphs, in: L. Lovasz (ed.), Graph theory and combinatorial biology; Proc. Int. Colloqu. Balatonlelle (Hungary) 1996, Bolyai Soc. Math. Studies 7 (Budapest, 1999) 333-362.
- F.S. Roberts amd J.E. Steif, A characterization of competition graphs of arbitrary digraphs, Discrete Appl. Math. 6 (1983) 323-326, doi: 10.1016/0166-218X(83)90087-2.
- M. Sonntag, H.-M. Teichert, Competition hypergraphs, Discrete Appl. Math. 143 (2004) 324-329, doi: 10.1016/j.dam.2004.02.010.