Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A matrix with sums of Catalan numbers -- LU-decomposition and
  determinant
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph