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arXiv · 1308.5170

Forbidden Directed Minors and Kelly-width

Shiva Kintali·Qiuyi Zhang
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Abstract

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 K_3 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, K_3, N_4 and M_5.

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Shiva Kintali, Qiuyi Zhang. 2014-01-11. Forbidden Directed Minors and Kelly-width. https://arxiv.org/abs/1308.5170

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