It is well-known that the largest cycles of a graph may have empty intersection. This is the case, for example, for any hypohamiltonian graph. In the literature, several important classes of graphs have been shown to contain examples with the above property. This paper investigates a (nontrivial) cl
Simultaneous intersection representation of pairs of graphs
β Scribed by Tanenbaum, Paul J.
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 436 KB
- Volume
- 32
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
We characterize the pairs (G 1 , G 2 ) of graphs on a shared vertex set that are intersection polysemic: those for which the vertices may be assigned subsets of a universal set such that G 1 is the intersection graph of the subsets and G 2 is the intersection graph of their complements. We also consider several special cases and explore bounds on the size of the universal set.
π SIMILAR VOLUMES
In our efforts to study the niche graph of a tournament T , we have found it easier to study the complement, which we call the ''mixed pair'' graph of T and denote MP (T ). We show that an undirected graph G is MP (T ), for some tournament T , if and only if G is one of the following: a cycle of odd
The leafage of a digraph is the minimum number of leaves in a host tree in which it has a subtree intersection representation. We discuss bounds on the leafage in terms of other parameters (including Ferrers dimension), obtaining a string of sharp inequalities.
Given a BIBD S = (V, B), its 1-block-intersection graph GS has as vertices the elements of B; two vertices B1, B2 β B are adjacent in GS if |B1 β© B2| = 1. If S is a triple system of arbitrary index Ξ», it is shown that GS is hamiltonian.