Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Combinatorial Identity for Rooted Labeled Forests   In this brief note a straightforward combinatorial proof for an identity
directly connecting rooted forests and unordered set partitions is provided.
Furthermore, references that put this type of identity in the context of forest
volumes and multinomial identities are given.

17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics