Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Orchard crossing number of complete bipartite graphs   We compute the Orchard crossing number, which is defined in a similar way to
the rectilinear crossing number, for the complete bipartite graphs K_{n,n}.

6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg