Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generating Sets of an Infinite Semigroup of Transformations Preserving a
  Zig-zag Order   A zig-zag order is like a directed path, only with alternating directions. A
generating set of minimal size for the semigroup of all full transformations on
a finite set preserving the zig-zag order was determined by Fenandes et al. in
2019. This paper deals with generating sets of the semigroup $F_{\mathbb{N}}$
of all full transformations on the set of all natural numbers preserving the
zig-zag order. We prove that $F_{\mathbb{N}}$ has no minimal generating sets
and present two particular infinite decreasing chains of generating sets of
$F_{\mathbb{N}}$.

14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics