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On the interval number of a chordal graph

✍ Scribed by Edward R. Scheinerman


Publisher
John Wiley and Sons
Year
1988
Tongue
English
Weight
249 KB
Volume
12
Category
Article
ISSN
0364-9024

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✦ Synopsis


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 clique size w ( G ) = m, then i(G) d [l + o(l)]m/log, m and this result is best possible, even for split graphs (chordal graphs whose complement is also chordal).


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