  Some randomized algorithms, used to obtain a random $n^2 \times n^2$ Sudoku
matrix, where $n$ is a natural number, is reviewed in this study. Below is
described the set $\Pi_n$ of all $(2n) \times n$ matrices, consisting of
elements of the set $\mathbb{Z}_n =\{ 1,2,\ldots ,n\}$, such that every row is
a permutation. It is proved that such matrices would be particularly useful in
developing efficient algorithms in generating Sudoku matrices. An algorithm to
obtain random $\Pi_n$ matrices is presented in this paper. The algorithms are
evaluated according to two criteria - probability evaluation, and time
evaluation. This type of criteria is interesting from both theoretical and
practical point of view because they are particularly useful in the analysis of
computer programs.
