Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Fractional Diffusion Equations for Lattice and Continuum:
  Grunwald-Letnikov Differences and Derivatives Approach
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int