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20052026
most citedSimple permutations and algebraic generating functions

7 citations · 15 across the 21 of their papers we have counts for

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23 papers · 1 filter

math.CO2026

Majorization and additive tuples in

Sophie Huczynska, Firdavs Rakhmonov, Chi Hoi Yip

Majorization is a fundamental tool for comparing how "spread out" the entries of two vectors are. Key majorization results were obtained for the integers by Hardy, Littlewood and P…

math.CO2026

Cyclotomic skew partial difference sets and partial difference families

Sophie Huczynska, Tekgül Kalaycı

Skew partial difference sets (skew PDSs) are recently-introduced combinatorial objects closely related to partial difference sets (PDSs). To date, only one construction approach fo…

math.CO2026

Graph labellings and external difference families

Gavin Angus, Sophie Huczynska, Struan McCartney

Digraph-defined external difference families were recently introduced as a natural generalization of several well-studied combinatorial objects motivated by cryptography (e.g. exte…

math.CO2025

The Intersection Distribution: New Results and Perspectives

Sophie Huczynska, Lukas Klawuhn, Maura B. Paterson

Intersection distribution and non-hitting index are concepts introduced recently by Li and Pott as a new way to view the behaviour of a collection of finite field polynomials. With…

math.CO2025

Digraph-defined external difference families and new circular external difference families

Sophie Huczynska, Christopher Jefferson, Struan McCartney

External difference families (EDFs) are combinatorial objects which were introduced in the early 2000s, motivated by information security applications such as the construction of A…

math.CO2025

Strongly Regular Graphs with Generalized Denniston and Dual Generalized Denniston Parameters

Shuxing Li, James A. Davis, Sophie Huczynska +2

We construct two families of strongly regular Cayley graphs, or equivalently, partial difference sets, based on elementary abelian groups. The parameters of these two families are…

math.CO2024★ 1 cited

Optical orthogonal codes from a combinatorial perspective

Sophie Huczynska, Siaw-Lynn Ng

Optical orthogonal codes (OOCs) are sets of -sequences with good auto- and cross-correlation properties. They were originally introduced for use in multi-access communicatio…

math.CO2024

Additive triples in groups of odd prime order

Sophie Huczynska, Jonathan Jedwab, Laura Johnson

Let be an odd prime. For nontrivial proper subsets of of cardinality , respectively, we count the number of additive triples, namely elemen…

math.CO2024

New results on non-disjoint and classical strong external difference families

Sophie Huczynska, Sophie Hume

Classical strong external difference families (SEDFs) are much-studied combinatorial structures motivated by information security applications; it is conjectured that only one clas…

math.CO2023

Denniston partial difference sets exist in the odd prime case

James A. Davis, Sophie Huczynska, Laura Johnson +1

Denniston constructed partial difference sets (PDSs) with the parameters in ele…

math.CO2023

Non-disjoint strong external difference families can have any number of sets

Sophie Huczynska, Siaw-Lynn Ng

Strong external difference families (SEDFs) are much-studied combinatorial objects motivated by an information security application. A well-known conjecture states that only one ab…

math.CO2023

New constructions for disjoint partial difference families and external partial difference families

S. Huczynska, L. M. Johnson

Recently, new combinatorial structures called disjoint partial difference families (DPDFs) and external partial difference families (EPDFs) were introduced, which simultaneously ge…

math.CO2022

Internal and external partial difference families and cyclotomy

Sophie Huczynska, Laura Johnson

We introduce the concept of a disjoint partial difference family (DPDF) and an external partial difference family (EPDF), a natural generalisation of the much-studied structures of…

math.CO2019

Strong external difference families in abelian and non-abelian groups

Sophie Huczynska, Christopher Jefferson, Silvia Nepsinska

Strong external difference families (SEDFs) have applications to cryptography and are rich combinatorial structures in their own right; until now, all SEDFs have been in abelian gr…

math.CO2019

Characterising bimodal collections of sets in finite groups

Sophie Huczynska, Maura B. Paterson

A collection of disjoint subsets of a finite abelian group is said to have the \emph{bimodal} property if, for any non-zero group element , eit…

math.CO2018

Weighted external difference families and R-optimal AMD codes

Sophie Huczynska, Maura B. Paterson

In this paper, we provide a mathematical framework for characterizing AMD codes that are R-optimal. We introduce a new combinatorial object, the reciprocally-weighted external diff…

math.CO2016★ 1 cited

Existence and Non-Existence Results for Strong External Difference Families

Sophie Huczynska, Maura B. Paterson

We consider strong external difference families (SEDFs); these are external difference families satisfying additional conditions on the patterns of external diferences that occur,…

math.CO2016

On well quasi-order of graph classes under homomorphic image orderings

N. Ruskuc, Sophie Huczynska

In this paper we consider the question of well quasi-order for classes defined by a single obstruction within the classes of all graphs, digraphs and tournaments, under the homomor…

math.CO2011

Beyond sum-free sets in the natural numbers

Sophie Huczynska

For an interval [1,N] in the natural numbers, investigating subsets S of [1,N] such that |{(x,y) in S^2:x+y in S}|=0, known as sum-free sets, has attracted considerable attention.…

math.CO2006★ 7 cited

Simple permutations and algebraic generating functions

Robert Brignall, Sophie Huczynska, Vincent Vatter

A simple permutation is one that does not map a nontrivial interval onto an interval. It was recently proved by Albert and Atkinson that a permutation class with only finitely simp…

math.CO2006★ 6 cited

Decomposing simple permutations, with enumerative consequences

Robert Brignall, Sophie Huczynska, Vince Vatter

We prove that every sufficiently long simple permutation contains two long almost disjoint simple subsequences. This result has applications to the enumeration of restricted permut…

math.CO2006

Grid classes and the Fibonacci dichotomy for restricted permutations

Sophie Huczynska, Vincent Vatter

We introduce and characterise grid classes, which are natural generalisations of other well-studied permutation classes. This characterisation allows us to give a new, short proof…

math.CO2005

Frequency permutation arrays

Sophie Huczynska, Gary L. Mullen

Motivated by recent interest in permutation arrays, we introduce and investigate the more general concept of frequency permutation arrays (FPAs). An FPA of length n=m lambda and di…