Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $\mathcal{H}$-matrix approximability of inverses of discretizations of
  the fractional Laplacian   The integral version of the fractional Laplacian on a bounded domain is
discretized by a Galerkin approximation based on piecewise linear functions on
a quasi-uniform mesh. We show that the inverse of the associated stiffness
matrix can be approximated by blockwise low-rank matrices at an exponential
rate in the block rank.

5
The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol