Tree-width of graphs and surface duality
نویسنده
چکیده
In Graph Minors III, Robertson and Seymour conjecture that the tree-width of a graph and that of its dual differ by at most one. In this paper, we prove that given a hypergraph H on a surface of Euler genus k, the tree-width of H∗ is at most the maximum of tw(H) + 1 + k and the maximum size of a hyperedge of H∗ minus one.
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ورودعنوان ژورنال:
- Electronic Notes in Discrete Mathematics
دوره 32 شماره
صفحات -
تاریخ انتشار 2009