Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral functions of the simplest even order ordinary differential
  operator   We consider the minimal differential operator A generated in $L^2(0,\infty)$
by the differential expression $l(y) = (-1)^n y^{(2n)}$. Using the technique of
boundary triplets and the corresponding Weyl functions, we find explicit form
of the characteristic matrix and the corresponding spectral function for the
Friedrichs and Krein extensions of the operator A.

13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio