Results 41 to 50 of about 21,091,768 (168)

Context‐free graphs and their transition groups

Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract Starting from context‐free inverse graphs, we introduce a new class of groups and study their structural properties. We establish closure properties, show that their coword problems are context‐free, analyze torsion elements, and realize them as subgroups of the asynchronous rational group.
Daniele D'Angeli, Francesco Matucci, Davide Perego, Emanuele Rodaro   +3 more
wiley   +1 more source

SPERNER THEOREMS FOR UNRELATED COPIES OF POSETS AND GENERATING DISTRIBUTIVE LATTICES

Ural Mathematical Journal
For a finite poset (partially ordered set) \(U\) and a natural number \(n\), let \(S(U,n)\) denote the largest number of pairwise unrelated copies of  \(U\) in the powerset lattice (AKA subset lattice) of an \(n\)-element set.
Gábor Czédli
doaj   +1 more source

Subpullbacks and coproducts of $S$-posets [PDF]

Categories and General Algebraic Structures with Applications, 2015
In 2001, S. Bulman-Fleming et al. initiated the study of three flatness properties (weakly kernel flat, principally weakly kernel flat, translation kernel flat) of right acts $A_{S}$ over a monoid $S$ that can be described by means of when the functor ...
Xingliang Liang, Yanfeng Luo
doaj  

A Min–Max Relation on Dicuts and Dijoins in Weighted Chordal Digraphs

Journal of Graph Theory, Volume 113, Issue 3, Page 462-469, November 2026.
ABSTRACT In a digraph, a dicut is a cut where all the arcs cross in one direction. A dijoin is a subset of arcs that intersects every dicut. Edmonds and Giles conjectured that in a weighted digraph, the minimum weight of a dicut is equal to the maximum size of a packing of dijoins. This has been disproved. However, the unweighted version conjectured by
Gérard Cornuéjols, Siyue Liu, R. Ravi
wiley   +1 more source

Weighted partitions [PDF]

Discrete Mathematics & Theoretical Computer Science, 2013
In this extended abstract we consider the poset of weighted partitions Π _n^w, introduced by Dotsenko and Khoroshkin in their study of a certain pair of dual operads.
Rafael González S. D'León, Michelle L. Wachs   +1 more
doaj   +1 more source

Signed Projective Cubes, a Homomorphism Point of View

Journal of Graph Theory, Volume 113, Issue 1, Page 38-56, September 2026.
ABSTRACT The (signed) projective cubes, as a special class of graphs closely related to the hypercubes, are on the crossroad of geometry, algebra, discrete mathematics and linear algebra. Defined as Cayley graphs on binary groups, they represent basic linear dependencies.
Meirun Chen, Reza Naserasr, Alessandra Sarti   +2 more
wiley   +1 more source

New Hopf Structures on Binary Trees [PDF]

Discrete Mathematics & Theoretical Computer Science, 2009
The multiplihedra $\mathcal{M}_{\bullet} = (\mathcal{M}_n)_{n \geq 1}$ form a family of polytopes originating in the study of higher categories and homotopy theory. While the multiplihedra may be unfamiliar to the algebraic combinatorics community, it is
Stefan Forcey, Aaron Lauve, Frank Sottile   +2 more
doaj   +1 more source

On a criterion of the finiteness of the representation type for families of the categories of injective representations

Науковий вісник Ужгородського університету. Серія: Математика і інформатика, 2022
The representations of posets (partially ordered sets), introduced by L. A. Nazarova and A. V. Roiter in 1972, play an important role in the modern representation theory and its applications. M. M.
В. М. Бондаренко, М. В. Стьопочкіна   +1 more
doaj   +1 more source

A Linear Generalization of the Nearly Gorenstein Property, With Applications to Veronese Subalgebras

Mathematische Nachrichten, Volume 299, Issue 9, Page 2436-2451, September 2026.
ABSTRACT We study the nearly Gorenstein property for Veronese subalgebras of (semi‐)standard graded algebras. We introduce a condition (♮)$(\natural)$ for Cohen–Macaulay semi‐standard graded rings, motivated by the study of Ehrhart rings. We show that if a semi‐standard graded algebra R$ R$ satisfies (♮)$(\natural)$, then its Veronese subalgebras R(k)$
Sora Miyashita
wiley   +1 more source

Stone space partitions indexed by a poset [PDF]

, 2022
Stone space partitions $\{X_{p}\mid p\in P\}$ satisfying conditions like $\bar{X_{p}}=\bigcup_{q\leqslant p}X_{q}$ for all $p\in P$, where $P$ is a poset or PO system (poset with a distinguished subset), arise naturally in the study both of primitive ...
Apps, Andrew
core   +1 more source