Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Oscillation of linear ordinary differential equations: on a theorem by
  A. Grigoriev   We give a simplified proof and an improvement of a recent theorem by A.
Grigoriev, placing an upper bound for the number of roots of linear
combinations of solutions to systems of linear equations with polynomial or
rational coefficients.

22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg