Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Decentralized Spectrum Access System: Vision, Challenges, and a
  Blockchain Solution
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph