Classes of graphs with restricted interval models
نویسندگان
چکیده
We introduce -proper interval graphs as interval graphs with interval models in which no interval is properly contained in more than other intervals, and also provide a forbidden induced subgraph characterization of this class of graphs. We initiate a graph-theoretic study of subgraphs of -proper interval graphs with maximum clique size and give an equivalent characterization of these graphs by restricted path-decomposition. By allowing the parameter to vary from 0 to , we obtain a nested hierarchy of graph families, from graphs of bandwidth at most to graphs of pathwidth at most . Allowing both parameters to vary, we have an infinite lattice of graph classes ordered by containment.
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عنوان ژورنال:
- Discrete Mathematics & Theoretical Computer Science
دوره 3 شماره
صفحات -
تاریخ انتشار 1999