Pseudo-Interval Graphs
โ Scribed by Erik O. Brauner; Richard A. Brauldi; Elizabeth S. N. Sneyd
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 431 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
We study a class of perfect graphs which, because they generalize interval graphs, we call pseudoโinterval graphs. Like interval graphs, their vertices correspond to intervals of a linearly ordered set, but a modified definition of intersection is used in order to determine edges. The complements of pseudoโinterval graphs are comparability graphs but unlike interval graphs, pseudoโinterval graphs are only weakly triangulated. We characterize trees and complements of trees which are pseudoโinterval graphs. Finally we determine all minimal nonโpseudointerval graphs on eight or fewer vertices whose complements are comparability graphs and which are weakly triangulated. ยฉ 1995 John Wiley & Sons; Inc.
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