Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Partition Function for Two-Dimensional Nearest Neighbour Ising Model in
  a Non-Zero Magnetic Field for a Square Lattice of 16 Sites   An explicit expression for the partition function of two-dimensional nearest
neighbour Ising models in the presence of a magnetic field is derived by a
systematic enumeration of all the spin configurations pertaining to a square
lattice of sixteen sites. The critical temperature is shown to be in excellent
agreement with the reported values while the corresponding dimensionless
magnetic field is obtained as 0.004.

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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: astro-ph
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat