Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Invariant subspaces of powers of some unicellular operators   In this paper we study subspaces which are invariant under squares and cubes
(separately as well as jointly) of unicellular backward weighted shift
operators on a separable Hilbert space. The finite-dimensional subspaces are
characterized for all weights and the infinite-dimensional subspaces are
characterized for two classes of weights.

10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs