Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the excluded minor structure theorem for graphs of large treewidth   At the core of the Robertson-Seymour theory of graph minors lies a powerful
structure theorem which captures, for any fixed graph H, the common structural
features of all the graphs not containing H as a minor. Robertson and Seymour
prove several versions of this theorem, each stressing some particular aspects
needed at a corresponding stage of the proof of the main result of their
theory, the graph minor theorem.
  We prove a new version of this structure theorem: one that seeks to combine
maximum applicability with a minimum of technical ado, and which might serve as
a canonical version for future applications in the broader field of graph minor
theory. Our proof departs from a simpler version proved explicitly by Robertson
and Seymour. It then uses a combination of traditional methods and new
techniques to derive some of the more subtle features of other versions as well
as further useful properties, with substantially simplified proofs.

6
The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
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The categories of this paper are: q-bio
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: nlin
29
The categories of this paper are: funct-an