On the Complements of Partial k-Trees
نویسندگان
چکیده
We introduce new techniques for studying the structure of partial k-trees. In particular, we show that the complements of partial k-trees provide an intuitively-appealing characterization of partial k-tree obstructions. We use this characterization to obtain a lower bound of 2 (k log k) on the number of obstructions, signi cantly improving the previously best-known bound of 2 ( p . Our techniques have the added advantage of being considerably simpler than those of previous authors.
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