Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improving a method for the study of limit cycles of the Lienard equation   In recent papers we have introduced a method for the study of limit cycles of
the Lienard system: dot{x}=y-F(x), dot{y}=-x, where F(x) is an odd polynomial.
The method gives a sequence of polynomials R_n(x), whose roots are related to
the number and location of the limit cycles, and a sequence of algebraic
approximations to the bifurcation set of the system. In this paper, we present
a variant of the method that gives very important qualitative and quantitative
improvements.

14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex