Forbidden directed minors and Kelly-width
نویسندگان
چکیده
Partial 1-trees are undirected graphs of treewidth at most one. Similarly, partial 1-DAGs are directed graphs of KellyWidth at most two. It is well-known that an undirected graph is a partial 1-tree if and only if it has no K3 minor. In this paper, we generalize this characterization to partial 1-DAGs. We show that partial 1-DAGs are characterized by three forbidden directed minors, K3, N4 and M5.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 662 شماره
صفحات -
تاریخ انتشار 2017