Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cancellable elements of the lattices of varieties of semigroups and
  epigroups   We completely determine all semigroup [epigroup] varieties that are
cancellable elements of the lattice of all semigroup [respectively epigroup]
varieties.

10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th