Displaying 61 – 80 of 146

Showing per page

Le module dendriforme sur le groupe cyclique

Frédéric Chapoton (2008)

Annales de l’institut Fourier

La structure d’opérade anticyclique de l’opérade dendriforme donne en particulier une matrice d’ordre n agissant sur l’espace engendré par les arbres binaires plans à n feuilles. On calcule le polynôme caractéristique de cette matrice. On propose aussi une conjecture compatible pour le polynôme caractéristique de la transformation de Coxeter du poset de Tamari, qui est essentiellement une racine carrée de cette matrice.

Macaulay posets.

Bezrukov, Sergei L., Leck, Uwe (2004)

The Electronic Journal of Combinatorics [electronic only]

Noncommutative extensions of the Fourier transform and its logarithm

Romuald Lenczewski (2002)

Studia Mathematica

We introduce noncommutative extensions of the Fourier transform of probability measures and its logarithm to the algebra (S) of complex-valued functions on the free semigroup S = FS(z,w) on two generators. First, to given probability measures μ, ν with all moments finite, we associate states μ̂, ν̂ on the unital free *-bialgebra (ℬ,ε,Δ) on two self-adjoint generators X,X’ and a projection P. Then we introduce and study cumulants which are additive under the convolution μ̂* ν̂ = μ̂ ⊗ ν̂ ∘ Δ when...

On CCC boolean algebras and partial orders

András Hajnal, István Juhász, Zoltán Szentmiklóssy (1997)

Commentationes Mathematicae Universitatis Carolinae

We partially strengthen a result of Shelah from [Sh] by proving that if κ = κ ω and P is a CCC partial order with e.g. | P | κ + ω (the ω th successor of κ ) and | P | 2 κ then P is κ -linked.

On colored set partitions of type B n

David Wang (2014)

Open Mathematics

Generalizing Reiner’s notion of set partitions of type B n, we define colored B n-partitions by coloring the elements in and not in the zero-block respectively. Considering the generating function of colored B n-partitions, we get the exact formulas for the expectation and variance of the number of non-zero-blocks in a random colored B n-partition. We find an asymptotic expression of the total number of colored B n-partitions up to an error of O(n −1/2log7/2 n], and prove that the centralized and...

On distances and metrics in discrete ordered sets

Stephan Foldes, Sándor Radelecki (2021)

Mathematica Bohemica

Discrete partially ordered sets can be turned into distance spaces in several ways. The distance functions may or may not satisfy the triangle inequality and restrictions of the distance to finite chains may or may not coincide with the natural, difference-of-height distance measured in a chain. It is shown that for semilattices the semimodularity ensures the good behaviour of the distances considered. The Jordan-Dedekind chain condition, which is weaker than semimodularity, is equivalent to the...

Currently displaying 61 – 80 of 146