Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tridiagonalization and the Heun equation   It is shown that the tridiagonalization of the hypergeometric operator $L$
yields the generic Heun operator $M$. The algebra generated by the operators
$L,M$ and $Z=[L,M]$ is quadratic and a one-parameter generalization of the
Racah algebra. The new Racah-Heun orthogonal polynomials are introduced as
overlap coefficients between the eigenfunctions of the operators $L$ and $M$.
An interpretation in terms of the Racah problem for $su(1,1)$ algebras and
separation of variables in a superintegrable system are discussed.

32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat