Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hausdorff operators on Lebesgue spaces with positive definite
  perturbation matrices are non-Riesz   We consider generalized Hausdorff operators with positive definite and
permutable perturbation matrices on Lebesgue spaces and prove that such
operators are not Riesz operators provided they are non-zero.

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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-th
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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: astro-ph
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The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th