Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Counting Subrings of ${\mathbb Z}^n$ of finite index   In this article we investigate the number of subrings of $\Z^d$ using subring
zeta functions and $p$-adic integration.

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The categories of this paper are: hep-th
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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: supr-con
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The categories of this paper are: cs
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin