Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Serendipity and the SDSS: Discovery of the Largest Known Planetary
  Nebula on the Sky
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph