The interval number of a (simple, undirected) graph G is the least positive integer t such that G is the intersection graph of sets, each of which is the union of t real intervals. A chordal (or triangulated) graph is one with no induced cycles on 4 or more vertices. If G is chordal and has maximum
On the chordality of a graph
β Scribed by Terry A. McKee; Edward R. Scheinerman
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 574 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
The chordality of a graph G = (V, E) is defined as the minimum k such that we can write E = E~1~ β© β¦ β© E~k~ with each (V, E~i~) a chordal graph. We present several results bounding the value of this generalization of boxicity. Our principal result is that the chordality of a graph is at most its tree width. In particular, seriesβparallel graphs have chordality at most 2. Potential strengthenings of this statement fail in that there are planar graphs with chordality 3 and seriesβparallel graphs with boxicity 3. Β© 1993 John Wiley & Sons, Inc.
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