Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lions and contamination, triangular grids, and Cheeger constants   Suppose each vertex of a graph is originally occupied by contamination,
except for those vertices occupied by lions. As the lions wander on the graph,
they clear the contamination from each vertex they visit. However, the
contamination simultaneously spreads to any adjacent vertex not occupied by a
lion. How many lions are required in order to clear the graph of contamination?
We give a lower bound on the number of lions needed in terms of the Cheeger
constant of the graph. Furthermore, the lion and contamination problem has been
studied in detail on square grid graphs by Brass et al. and Berger et al., and
we extend this analysis to the setting of triangular grid graphs.

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The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ