Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Drinfeld modular curves have many points   Ihara's proof that the reduction of the modular curve $X_0(n)$ at a prime $p$
not dividing $n$ has many points over a quadratic extension is adapted to the
drinfeld modular curves $X_0(n)$. In order to do so, some properties of
drinfeld modular varieties that have no proof in the literature are proven. The
text is more or less self-contained.

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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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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: nlin
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The categories of this paper are: physics
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The categories of this paper are: astro-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th