Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Crossed product of a C*-algebra by an endomorphism, coefficient algebras
  and transfer operators
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con