D. Kreher

activity

20192026

most citedBlock-avoiding sequencings of points in Steiner triple systems

3 citations · 3 across the 6 of their papers we have counts for

collaborators

9 papers

math.GR2026

The theory of $(λ, μ)$ -fold factorizations of groups

Donald L. Kreher, Shuxing Li, Douglas R. Stinson

Motivated by recent work on $λ$ -fold near-factorizations by Kreher, Li, and Stinson (Designs, Codes and Cryptography, 2026), we introduce and systematically investigate $(λ, μ)$ -fol…

math.GR2025

$λ$ -fold near-factorizations of groups

Donald L. Kreher, Shuxing Li, Douglas R. Stinson

We initiate the study of $λ$ -fold near-factorizations of groups with $λ > 1$ . While $λ$ -fold near-factorizations of groups with $λ = 1$ have been studied in numerous papers, this is…

math.GR2024

Uniqueness and explicit computation of mates in near-factorizations

Donald L. Kreher, William J. Martin, Douglas R. Stinson

We show that a "mate'' $B$ of a set $A$ in a near-factorization $(A, B)$ of a finite group $G$ is unique. Further, we describe how to compute the mate $B$ very efficiently using an…

math.GR2024

Near-factorizations of dihedral groups

Donald L. Kreher, Maura B. Paterson, Douglas R. Stinson

We investigate near-factorizations of nonabelian groups, concentrating on dihedral groups. We show that some known constructions of near-factorizations in dihedral groups yield equ…

math.CO2024

Strong External Difference Families and Classification of $α$ -valuations

Donald L. Kreher, Maura B. Paterson, Douglas R. Stinson

One method of constructing $(a^{2} + 1, 2, a, 1)$ -SEDFs (i.e., strong external difference families) in $Z_{a^{2} + 1}$ makes use of $α$ -valuations of complete bipartite graphs $K_{…

math.CO2024

Nestings of BIBDs with block size four

Marco Buratti, Donald L. Kreher, Douglas R. Stinson

In a nesting of a balanced incomplete block design (or BIBD), we wish to add a point (the \emph{nested point}) to every block of a $(v, k, λ)$ -BIBD in such a way that we end up with…

math.NT2024

On min-base palindromic representations of powers of 2

Donald L. Kreher, Douglas R. Stinson

A positive integer $N$ is \emph{palindromic in the base $b$ } when $N = \sum_{i = 0}^{k} c_{i} b^{i}$ , $c_{k} \neq = 0$ ,and $c_{i} = c_{k - i}, i = 0, 1, 2, ..., k$ , Focusing on powers of 2, we investig…

cs.IT2022

Constructions and bounds for codes with restricted overlaps

Simon R. Blackburn, Navid Nasr Esfahani, Donald L. Kreher +1

Non-overlapping codes have been studied for almost 60 years. In such a code, no proper, non-empty prefix of any codeword is a suffix of any codeword. In this paper, we study codes…

math.CO2019★ 3 cited

Block-avoiding sequencings of points in Steiner triple systems