Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crossing numbers of periodic graphs   A graph is periodic if it can be obtained by joining identical pieces in a
cyclic fashion. It is shown that the limit crossing number of a periodic graph
is computable. This answers a question of Benny Pinontoan and Bruce Richter
(2004).

18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph