Contraction and Treewidth Lower Bounds
نویسندگان
چکیده
منابع مشابه
Contraction and Treewidth Lower Bounds
Edge contraction is shown to be a useful mechanism to improve lower bound heuristics for treewidth. A successful lower bound for treewidth is the degeneracy: the maximum over all subgraphs of the minimum degree. The degeneracy is polynomial time computable. We introduce the notion of contraction degeneracy: the maximum over all minors of the minimum degree. We show that the contraction degenera...
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Let F be a family of graphs and f be a function from F to positive integer set N . wF ,f (G) = min {f(H) : There exists a H ∈ F such that G is a subgraph of H} is called (F , f)-width. Many graph parameters, such as bandwidth, pathwidth, treewidth and profile, can be defined by this method by selecting different F and f . Based on method in [8] proposed by Zhou, we give a systematic method for ...
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ژورنال
عنوان ژورنال: Journal of Graph Algorithms and Applications
سال: 2006
ISSN: 1526-1719
DOI: 10.7155/jgaa.00117