Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Optimization of inhomogeneous electron correlation factors in periodic
  solids
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas