Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Umbral Methods and Harmonic Numbers   The theory of harmonic based function is discussed here within the framework
of umbral operational methods. We derive a number of results based on
elementary notions relying on the properties of Gaussian integrals.

29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc