Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An application of a moment problem to completely monotonic functions   We consider the following question: if a function of the form
$\int_0^{\infty}\varphi(t)\, e^{-xt}dt$ is completely monotonic, is it then
$\varphi\ge0$? It turns out that the question is related to a moment problem.
In the end we apply those results to answer some questions concerning complete
monotonicity of certain functions raised in F. Qi and R. Agarwal, \textit{On
complete monotonicity for several classes of functions related to ratios of
gamma functions}, J. Inequal. Appl. (2019).

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The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
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The categories of this paper are: eess
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an