Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Strong electron-phonon coupling in the rare-earth carbide superconductor
  La2C3
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ