Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Further results and examples for formal mathematical systems with
  structural induction   In the former article "Formal mathematical systems including a structural
induction principle" we have presented a unified theory for formal mathematical
systems including recursive systems closely related to formal grammars,
including the predicate calculus as well as a formal induction principle. In
this paper we present some further results and examples in order to illustrate
how this theory works.

7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg