Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Shepherdson's theorems for fragments of open induction   By a well-known result of Shepherdson, models of the theory IOpen (a first
order arithmetic containing the scheme of induction for all quantifier free
formulas) are exactly all the discretely ordered semirings that are integer
parts of their real closures. In this paper we prove several analogous results
that provide algebraic equivalents to various fragments of IOpen.

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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: physics