Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Finite Modules over $\Bbb Z[t,t^{-1}]$   Let $\Lambda=\Bbb Z[t,t^{-1}]$ be the ring of Laurent polynomials over $\Bbb
Z$. We classify all $\Lambda$-modules $M$ with $|M|=p^n$, where $p$ is a primes
and $n\le 4$. Consequently, we have a classification of Alexander quandles of
order $p^n$ for $n\le 4$.

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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: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
1
The categories of this paper are: cs
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The categories of this paper are: alg-geom
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
3
The categories of this paper are: physics
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The categories of this paper are: chao-dyn