[HTML][HTML] On the Terwilliger algebra of distance-biregular graphs

B Fernández, Š Miklavič - Linear Algebra and its Applications, 2020 - Elsevier
Let Γ denote a distance-biregular graph with vertex set X. Fix x∈ X and let T= T (x) denote
the Terwilliger algebra of Γ with respect to x. In this paper we consider irreducible T-modules …

On (almost) 2-Y-homogeneous distance-biregular graphs

B Fernández, S Penjić - Bulletin of the Malaysian Mathematical Sciences …, 2023 - Springer
Let Γ denote a bipartite graph with vertex set X and color partitions Y, Y′. For a nonnegative
integer i and a vertex x∈ X, let Γ i (x) denote the set of vertices in X that are at distance i from …

On bipartite graphs with exactly one irreducible T-module with endpoint 1, which is thin

B Fernández, Š Miklavič - European Journal of Combinatorics, 2021 - Elsevier
Let Γ denote a finite, simple, connected and bipartite graph. Fix a vertex x of Γ and let T= T
(x) denote the Terwilliger algebra of Γ with respect to x. Assume that x is a distance …

Certain graphs with exactly one irreducible T-module with endpoint 1, which is thin

B Fernández - Journal of Algebraic Combinatorics, 2022 - Springer
Let Γ denote a finite, simple and connected graph. Fix a vertex x of Γ and let T= T (x) denote
the Terwilliger algebra of Γ with respect to x. Assume that x is a distance-regularized vertex …

Almost Commutative Terwilliger Algebras of Group Association Schemes I: Classification

NL Bastian, SP Humphries - arXiv preprint arXiv:2409.09167, 2024 - arxiv.org
Terwilliger algebras are a subalgebra of a matrix algebra that are constructed from
association schemes over finite sets. In 2010, Rie Tanaka defined what it means for a …

[图书][B] Terwilliger Algebras for Several Finite Groups

NL Bastian - 2021 - search.proquest.com
In this thesis, we will explore the structure of Terwilliger algebras over several different types
of finite groups. We will begin by discussing what a Schur ring is, as well as providing many …

On standard bases of irreducible modules of Terwilliger algebras of Doob schemes

JVS Morales - Journal of Algebraic Combinatorics, 2023 - Springer
For integers n≥ 1 and m≥ 0, let D= D (n, m) denote the Doob scheme which is the direct
product of n copies of Shrikhande graph and m copies of complete graph on four vertices …

Certain graphs with exactly one irreducible -module with endpoint , which is thin: the pseudo-distance-regularized case

B Fernández - arXiv preprint arXiv:2301.10143, 2023 - arxiv.org
Let $\Gamma $ denote a finite, simple and connected graph. Fix a vertex $ x $ of $\Gamma $
which is not a leaf and let $ T= T (x) $ denote the Terwilliger algebra of $\Gamma $ with …

On symmetric association schemes and associated quotient-polynomial graphs

MA Fiol, S Penjić - Algebraic Combinatorics, 2021 - numdam.org
Let Γ denote an undirected, connected, regular graph with vertex set X, adjacency matrix A,
and d+ 1 distinct eigenvalues. Let A= A (Γ) denote the subalgebra of MatX (C) generated by …

[PDF][PDF] On the Terwilliger algebra of a certain family of bipartite distance-regular graphs with∆ 2= 0

Š Miklavic, S Penjic - Art Discrete Appl. Math, 2020 - academia.edu
Let Γ denote a bipartite distance-regular graph with diameter D≥ 4 and valency k≥ 3. Let X
denote the vertex set of Γ, and let Ai (0≤ i≤ D) denote the distance matrices of Γ. We …