Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fixed point theorem for an infinite Toeplitz matrix and its extension to
  general infinite matrices   In [V. M. Abramov, \emph{Bull. Aust. Math. Soc.} \textbf{104} (2021),
108--117] the fixed point equation for an infinite nonnegative Toeplitz matrix
has been studied. It was found the conditions for existence of a positive
solution and bounded positive solution. However, the proof of the existence of
a positive solution was entirely straightforward, not admitting extensions for
more general types of matrices. In the present note, we provide an alternative
proof for the existence of a positive solution in more general case. The
presented proof is based on an application of the fixed point theorem of M. A.
Krasnosel'skii. The results are then extended for the equations with infinite
matrices of a general type.

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The categories of this paper are: cond-mat
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg
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The categories of this paper are: cs
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: q-bio
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
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The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an