Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crossed morphisms, (integration of) post-Lie algebras and the post-Lie
  Magnus expansion   In the first part of this letter it will be shown that the post-Lie Magnus
expansion can be interpreted as a crossed morphism between two (local) Lie
group. The second part will be devoted to present two combinatorial methods,
both based on special tubings on planar trees, to compute the coefficients of
this remarkable formal series.

33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom