Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A simple proof of the characteristic function of Student's
  $t$-distribution   This note presents a simple proof of the characteristic function of Student's
$t$-distribution. The method of proof, which involves finding a differential
equation satisfied by the characteristic function, is applicable to many other
distributions.

33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat