The Tree-Width Compactness Theorem for Hypergraphs
نویسنده
چکیده
A hypergraph H has tree-width k (a notion introduced by Robertson and Seymour) if k is the least integer such that H admits a tree-decomposition of tree-width k. We prove a compactness theorem for this notion, that is, if every finite subhypergraph of H has tree-width < k, then H itself has tree-width < k. This result will be used in a later paper on well-quasi-ordering infinite graphs.
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تاریخ انتشار 1988