Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Perturbation-Iteration Algorithm for System of Fractional
  Differential Equations   In this study, perturbation-iteration algorithm, namely PIA, is applied to
solve some types of system of fractional differential equations (FDEs) for the
first time. To illustrate the efficiency of the method, numerical solutions are
compared with the results published in the literature by considering some FDEs.
The results confirm that the PIA is powerful, simple and reliable method for
solving system of nonlinear fractional differential equations.

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The categories of this paper are: acc-phys
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The categories of this paper are: eess
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
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The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
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The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn