Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 3D Ising System in an External Field. Recurrence Relations for the
  Asymmetric $\rho^6$ Model   The 3D one-component spin system in an external magnetic field is studied
using the collective variables method. The integration of the partition
function of the system over the phase space layers is performed in the
approximation of the sextic measure density including the even and the odd
powers of the variable (the asymmetric $\rho^6$ model). The general recurrence
relations between the coefficients of the effective measure densities are
obtained. The new functions appearing in these recurrence relations are given
in the form of a convergent series.

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The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex