Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A note on boundedness of the Hardy-Littlewood maximal operator on Morrey
  spaces   In this paper we prove that the Hardy-Littlewood maximal operator is bounded
on Morrey spaces $\mathcal{M}_{1,\lambda}(\rn)$, $0 \le \la < n$ for radial,
decreasing functions on $\rn$

30
The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-th
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The categories of this paper are: nlin
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The categories of this paper are: gr-qc