Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On certain diophantine equations related to triangular and tetrahedral
  numbers   In this paper we give solutions of certain diophantine equations related to
triangular and tetrahedral numbers and propose several problems connected with
these numbers.
  The material of this paper was presented in part at the 11th International
Workshop for Young Mathematicians - NUMBER THEORY, Krak\'{o}w, 14th-20th
september 2008.

4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con