Results 101 to 110 of about 887,797 (265)
Extensions of Steiner Triple Systems
Journal of Combinatorial Designs, Volume 33, Issue 3, Page 94-108, March 2025.ABSTRACT In this article, we study extensions of Steiner triple systems by means of the associated Steiner loops. We recognize that the set of Veblen points of a Steiner triple system corresponds to the center of the Steiner loop. We investigate extensions of Steiner loops, focusing in particular on the case of Schreier extensions, which provide a ...
Giovanni Falcone +2 more
wiley +1 more source
Sorting probability for large Young diagrams
Discrete Analysis, 2021 Sorting probability for large Young diagrams, Discrete Analysis 2021:24, 57 pp. Let $P=(X,\leq_P)$ be a finite partially ordered set (or _poset_, for short). A _linear extension_ $L$ of $P$ is a total ordering $\leq_L$ on $X$ such that for every $x,y\in
Swee Hong Chan, Igor Pak, Greta Panova
doaj +1 more source
Ibadan Lectures on Toric Varieties
, 2017 Toric varieties are perhaps the most accessible class of algebraic varieties. They often arise as varieties parameterized by monomials, and their structure may be completely understood through objects from geometric combinatorics.
Sottile, Frank
core
Baxter Algebras, Stirling Numbers and Partitions [PDF]
J. Algebra Appl. 4 (2005), 153-164, 2004 Recent developments of Baxter algebras have lead to applications to combinatorics, number theory and mathematical physics. We relate Baxter algebras to Stirling numbers of the first kind and the second kind, partitions and multinomial coefficients. This allows us to apply congruences from number theory to obtain congruences in Baxter algebras.
arxiv
On Quasi‐Hermitian Varieties in Even Characteristic and Related Orthogonal Arrays
Journal of Combinatorial Designs, Volume 33, Issue 3, Page 109-122, March 2025.ABSTRACT In this article, we study the BM quasi‐Hermitian varieties, laying in the three‐dimensional Desarguesian projective space of even order. After a brief investigation of their combinatorial properties, we first show that all of these varieties are projectively equivalent, exhibiting a behavior which is strikingly different from what happens in ...
Angela Aguglia +3 more
wiley +1 more source
Topology of matching complexes of complete graphs via discrete Morse theory [PDF]
Discrete Mathematics & Theoretical Computer ScienceBouc (1992) first studied the topological properties of $M_n$, the matching complex of the complete graph of order $n$, in connection with Brown complexes and Quillen complexes. Bj\"{o}rner et al. (1994) showed that $M_n$ is homotopically $(\nu_n-1)$
Anupam Mondal +2 more
doaj +1 more source
Feynman Diagrams in Algebraic Combinatorics
, 2002 We show, in great detail, how the perturbative tools of quantum field theory allow one to rigorously obtain: a ``categorified'' Faa di Bruno type formula for multiple composition, an explicit formula for reversion and a proof of Lagrange-Good inversion ...
Abdesselam, Abdelmalek
core +1 more source
Thom series of contact singularities [PDF]
, 2010 Thom polynomials measure how global topology forces singularities. The power of Thom polynomials predestine them to be a useful tool not only in differential topology, but also in algebraic geometry (enumerative geometry, moduli spaces) and algebraic ...
Fehér, L. M., Rimányi, R.
core
A generalization of boson normal ordering
, 2006 In this paper we define generalizations of boson normal ordering. These are based on the number of contractions whose vertices are next to each other in the linear representation of the boson operator function.
Bahns +13 more
core +1 more source
Higher order peak algebras [PDF]
Annals of Combinatorics 9:4 (2005), 411-430, 2004 Using the theory of noncommutative symmetric functions, we introduce the higher order peak algebras, a sequence of graded Hopf algebras which contain the descent algebra and the usual peak algebra as initial cases (N = 1 and N = 2). We compute their Hilbert series, introduce and study several combinatorial bases, and establish various algebraic ...
arxiv