Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Subtyping for F-Bounded Quantifiers and Equirecursive Types (Extended
  Version)   This paper defines a notion of binding trees that provide a suitable model
for second-order type systems with F-bounded quantifiers and equirecursive
types. It defines a notion of regular binding trees that correspond in the
right way to notions of regularity in the first-order case. It defines a notion
of subtyping on these trees and proves various properties of the subtyping
relation. It defines a mapping from types to trees and shows that types produce
regular binding trees. It presents a set of type equality and subtyping rules,
and proves them sound and complete with respect to the tree interpretation. It
defines a notion of binding-tree automata and how these generate regular
binding trees. It gives a polynomial-time algorithm for deciding when two
automata's trees are in the subtyping relation.

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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: physics
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The categories of this paper are: funct-an