South-West University "Neofit Rilski"

output

20082026

most citedUnstable states in dissociation of relativistic nuclei. Recent findings and prospects of researches

16 citations

researchers with a paper here

collaborating institutions

Showing math.COShow all

9 papers · 1 filter

math.CO2021★ 2 cited

Canonical matrices with entries integers modulo p

Krasimir Yordzhev

The work considers an equivalence relation in the set of all $n \times m$ matrices with entries in the set $[p] = {0, 1, \dots, p - 1}$ . In each element of the factor-set generated…

math.CO2016★ 2 cited

On the number of mutually disjoint pairs of S-permutation matrices

Krasimir Yordzhev

This work examines the concept of S-permutation matrices, namely $n^{2} \times n^{2}$ permutation matrices containing a single 1 in each canonical $n \times n$ subsquare (block). The a…

math.CO2015★ 1 cited

Calculation of the Number of all Pairs of Disjoint S-permutation Matrices

Krasimir Yordzhev

The concept of S-permutation matrix is considered. A general formula for counting all disjoint pairs of $n^{2} \times n^{2}$ S-permutation matrices as a function of the positive intege…

math.CO2014★ 2 cited

On the cardinality of a factor set in the symmetric group

Krasimir Yordzhev

Let $n$ be a positive integer, $σ$ be an element of the symmetric group $S_{n}$ and let $σ$ be a cycle of length $n$ . The elements $α, β \in S_{n}$ are $σ$ -equivalent…

math.CO2013★ 8 cited

Random Permutations, Random Sudoku Matrices and Randomized Algorithms

Krasimir Yordzhev

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 $Π_{n}$ of al…

math.CO2013★ 2 cited

Fibonacci sequence related to a combinatorial problem on binary matrices

Krasimir Yordzhev

We discuss an equivalence relation on the set of square binary matrices with the same number of 1's in each row and each column. Each binary matrix is represented using ordered n-t…