Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polynomial invariants of graphs on surfaces   For a graph embedded into a surface, we relate many combinatorial parameters
of the cycle matroid of the graph and the bond matroid of the dual graph with
the topological parameters of the embedding. This will give an expression of
the polynomial, defined by M.Las Vergnas in a combinatorial way using matroids
as a specialization of the Krushkal polynomial, defined using the symplectic
structure in the first homology group of the surface.

34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics