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arXiv · 1006.3167

Tree-width of hypergraphs and surface duality

Frédéric Mazoit
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Abstract

In Graph Minors III, Robertson and Seymour write: "It seems that the tree-width of a planar graph and the tree-width of its geometric dual are approximately equal - indeed, we have convinced ourselves that they differ by at most one". They never gave a proof of this. In this paper, we prove a generalisation of this statement to embedding of hypergraphs on general surfaces, and we prove that our bound is tight.

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Frédéric Mazoit. 2010-06-16. Tree-width of hypergraphs and surface duality. https://arxiv.org/abs/1006.3167

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