Treewidth Lower Bounds with Brambles
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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Article history: Received 22 September 2008 Revised 29 March 2009 Available online 19 April 2009
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ژورنال
عنوان ژورنال: Algorithmica
سال: 2007
ISSN: 0178-4617,1432-0541
DOI: 10.1007/s00453-007-9056-z