Roghayeh Maleki

activity

20202026

collaborators

26 papers

math.GR2026

Generating $\psl{2}{q}$ by elements of prime orders $2$ and $p$

Douglas Farenick, Roghayeh Maleki, Sofia Medina Varela +1

For primes $p \geq 5$ , we determine those $q$ for which the projective special linear group $\psl{2}{q}$ over the finite field of order $q$ is $(2, p)$ -generated -- that is, there ex…

math.OA2026

Representations of noncommutative cubes and prisms

Douglas Farenick, Roghayeh Maleki, Sofia Medina Varela +1

Representations of the operator system determined by the canonical generators of the free product of two cyclic groups of order $2$ and $k$ , or $d$ cyclic groups of order $2$ , are…

math.CO2025

On the second largest eigenvalue of certain graphs in the perfect matching association scheme

Himanshu Gupta, Allen Herman, Alice Lacaze-Masmonteil +2

The perfect matching association scheme is a set of relations on the perfect matchings of the complete graph on $2 n$ vertices. The relations between perfect matchings are defined b…

math.CO2025

The intersection densities of transitive actions of $PSL_{2} (q)$ with cyclic point stabilizers

Angelot Behajaina, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Given a finite transitive group $G \leq Sym Ω$ , the {intersection density} of $G$ is defined as the ratio between the size of the largest subsets of $G$ in which any t…

math.CO2025

On the Terwilliger algebras of quasi-thin Schurian association schemes

Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

An association scheme is triply transitive if its automorphism group is transitive, and the centralizer algebra of a point stabilizer of its automorphism group coincides with the T…

math.CO2025

On the $Q$ -polynomial property of bipartite graphs admitting a uniform structure

Blas Fernández, Roghayeh Maleki, Štefko Miklavič +1

Let $Γ$ denote a finite, connected graph with vertex set $X$ . Fix $x \in X$ and let $ε \geq 3$ denote the eccentricity of $x$ . For mutually distinct scalars $\{θ^*_i\}_{i=…

math.CO2024

On the Terwilliger algebra of the group association scheme of the symmetric group $sym (7)$

Allen Herman, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Terwilliger algebras are finite-dimensional semisimple algebras that were first introduced by Paul Terwilliger in 1992 in studies of association schemes and distance-regular graphs…

math.CO2024

On the $Q$ -polynomial property of the full bipartite graph of a Hamming graph

Blas Fernández, Roghayeh Maleki, Štefko Miklavič +1

The $Q$ -polynomial property is an algebraic property of distance-regular graphs, that was introduced by Delsarte in his study of coding theory. Many distance-regular graphs admit t…

math.CO2024

On the maximum intersecting sets of the general semilinear group of degree $2$

Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Let $p$ be a prime and $q = p^{k}$ . A subset $F \subset ΓL_{2} (q)$ is intersecting if any two semilinear transformations in $F$ agree on some non-z…

math.CO2023

On the Terwilliger algebra of the group association scheme of $C_{n} ⋊ C_{2}$

Roghayeh Maleki

In 1992, Terwilliger introduced the notion of the \emph{Terwilliger algebra} in order to study association schemes. The Terwilliger algebra of an association scheme $A$ i…

math.CO2023

The Erdős-Ko-Rado Theorem for non-quasiprimitive groups of degree $3 p$

Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

The \emph{intersection density} of a finite transitive group $G \leq Sym (Ω)$ is the rational number $ρ (G)$ given by the ratio between the maximum size of a subset of…

math.CO2023

Parameters of Quotient-Polynomial Graphs

Allen Herman, Roghayeh Maleki

Fiol has characterized quotient-polynomial graphs as precisely the connected graphs whose adjacency matrix generates the adjacency algebra of a symmetric association scheme. We sho…

math.CO2023

Distance-regular graphs with classical parameters that support a uniform structure: case $q \geq 2$

Blas Fernández, Roghayeh Maleki, Štefko Miklavič +1

Let $Γ = (X, R)$ denote a finite, simple, connected, and undirected non-bipartite graph with vertex set $X$ and edge set $R$ . Fix a vertex $x \in X$ , and define $\…

math.CO2023

On cocliques in commutative Schurian association schemes of the symmetric group

Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Given the symmetric group $G = Sym (n)$ and a multiplicity-free subgroup $H \leq G$ , the orbitals of the action of $G$ on $G / H$ by left multiplication induce a commuta…

math.CO2023

On the intersection spectrum of $PSL_{2} (q)$

Angelot Behajaina, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Given a group $G$ and a subgroup $H \leq G$ , a set $F \subset G$ is called $H$ \emph{-intersecting} if for any $g, g^{'} \in F$ , there exists $x H \in G / H$ such that $…

math.CO2023

The $q$ -Analogue of Zero Forcing for Certain Families of Graphs

Shaun Fallat, Neha Joshi, Roghayeh Maleki +6

Zero forcing is a combinatorial game played on a graph with the ultimate goal of changing the colour of all the vertices at minimal cost. Originally this game was conceived as a on…

math.CO2023

Distance-regular graphs with classical parameters that support a uniform structure: case $q \leq 1$

Blas Fernández, Roghayeh Maleki, Štefko Miklavič +1

Let $Γ = (X, R)$ denote a finite, simple, connected, and undirected non-bipartite graph with vertex set $X$ and edge set $R$ . Fix a vertex $x \in X$ , and define $\…

math.CO2022

On closed distance magic circulants of valency up to $5$

Blas Fernández, Roghayeh Maleki, Štefko Miklavič +1

Let $Γ = (V, E)$ be a graph of order $n$ . A {\em closed distance magic labeling} of $Γ$ is a bijection $ℓ : V \to {1, 2, \dots, n}$ for which there exists a positive integer $r$ …

math.CO2022

Intersection density of imprimitive groups of degree $pq$

Angelot Behajaina, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

A subset $F$ of a finite transitive group $G \leq Sym (Ω)$ is \emph{intersecting} if any two elements of $F$ agree on an element of $Ω$ . The \emph{…

math.CO2022

Applications of the Isolating Fusion Algorithm to Table Algebras and Association Schemes

Allen Herman, Roghayeh Maleki

Let $B$ be a basis for an $r$ -dimensional algebra $A$ over a field or commutative ring with unity. The semifusions of $B$ are the partitions of $B$ whose…

math.CO2022

On the intersection density of the symmetric group acting on uniform subsets of small size

Angelot Behajaina, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Given a finite transitive group $G \leq Sym (Ω)$ , a subset $F$ of $G$ is \emph{intersecting} if any two elements of $F$ agree on some element of $Ω…

math.CO2021

No Hilton-Milner type results for linear groups of degree two

Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

A set of permutations $F$ of a finite transitive permutation group $G \leq Sym (Ω)$ is \emph{intersecting} if any pair of elements of $F$ agree on…

math.CO2021

The search for small association schemes with noncyclotomic eigenvalues

Allen Herman, Roghayeh Maleki

In this article we determine feasible parameter sets for (what could potentially be) commutative association schemes with noncyclotomic eigenvalues that are of smallest possible ra…

math.CO2021

On non-normal subgroup perfect codes

Angelot Behajaina, Roghayeh Maleki, Andriaherimanana Sarobidy Razafimahatratra

Let $X = (V, E)$ be a graph. A subset $C \subseteq V (X)$ is a \emph{perfect code} of $X$ if $C$ is a coclique of $X$ with the property that any vertex in $V (X) ∖ C$ is adjace…

Generating $\psl{2}{q}$ by elements of prime orders 2 and p

Representations of noncommutative cubes and prisms

On the second largest eigenvalue of certain graphs in the perfect matching association scheme

The intersection densities of transitive actions of PSL2​(q) with cyclic point stabilizers

On the Terwilliger algebras of quasi-thin Schurian association schemes

On the Q-polynomial property of bipartite graphs admitting a uniform structure

On the Terwilliger algebra of the group association scheme of the symmetric group sym(7)

On the Q-polynomial property of the full bipartite graph of a Hamming graph

On the maximum intersecting sets of the general semilinear group of degree 2

On the Terwilliger algebra of the group association scheme of Cn​⋊C2​

The Erdős-Ko-Rado Theorem for non-quasiprimitive groups of degree 3p

Parameters of Quotient-Polynomial Graphs

Distance-regular graphs with classical parameters that support a uniform structure: case q≥2

On cocliques in commutative Schurian association schemes of the symmetric group

On the intersection spectrum of PSL2​(q)

The q-Analogue of Zero Forcing for Certain Families of Graphs

Distance-regular graphs with classical parameters that support a uniform structure: case q≤1

On closed distance magic circulants of valency up to 5

Intersection density of imprimitive groups of degree pq

Applications of the Isolating Fusion Algorithm to Table Algebras and Association Schemes

On the intersection density of the symmetric group acting on uniform subsets of small size

No Hilton-Milner type results for linear groups of degree two

The search for small association schemes with noncyclotomic eigenvalues

On non-normal subgroup perfect codes

Generating $\psl{2}{q}$ by elements of prime orders $2$ and $p$

The intersection densities of transitive actions of $PSL_{2} (q)$ with cyclic point stabilizers

On the $Q$ -polynomial property of bipartite graphs admitting a uniform structure

On the Terwilliger algebra of the group association scheme of the symmetric group $sym (7)$

On the $Q$ -polynomial property of the full bipartite graph of a Hamming graph

On the maximum intersecting sets of the general semilinear group of degree $2$

On the Terwilliger algebra of the group association scheme of $C_{n} ⋊ C_{2}$

The Erdős-Ko-Rado Theorem for non-quasiprimitive groups of degree $3 p$

Distance-regular graphs with classical parameters that support a uniform structure: case $q \geq 2$

On the intersection spectrum of $PSL_{2} (q)$

The $q$ -Analogue of Zero Forcing for Certain Families of Graphs

Distance-regular graphs with classical parameters that support a uniform structure: case $q \leq 1$

On closed distance magic circulants of valency up to $5$

Intersection density of imprimitive groups of degree $pq$