Let be the induced-minor relation. It is shown that, for every t, all chordal graphs of clique number at most t are well-quasi-ordered by . On the other hand, if the bound on clique number is dropped, even the class of interval graphs is not well-quasi-ordered by .
Restricted unimodular chordal graphs
β Scribed by Peled, Uri N.; Wu, Julin
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 176 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
A chordal graph is called restricted unimodular if each cycle of its vertex-clique incidence bipartite graph has length divisible by 4. We characterize these graphs within all chordal graphs by forbidden induced subgraphs, by minimal relative separators, and in other ways. We show how to construct them by starting from block graphs and multiplying vertices subject to a certain restriction, which leads to a linear-time recognition algorithm. We show how they are related to other classes such as distance-hereditary chordal graphs and strongly chordal graphs.
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