Results 31 to 40 of about 21,654,511 (186)
On homological classification of pomonoids by regular weak injectivity properties of S-posets
Open Mathematics, 2007 Abstract If S is a partially ordered monoid then a right S-poset is a poset A on which S acts from the right in such a way that the action is compatible both with the order of S and A. By regular weak injectivity properties we mean injectivity properties with respect to all regular monomorphisms (not all monomorphisms) from different ...
Zhang Xia, Laan Valdis
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A two-sided analogue of the Coxeter complex [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 For any Coxeter system (W, S) of rank n, we introduce an abstract boolean complex (simplicial poset) of dimension 2n − 1 which contains the Coxeter complex as a relative subcomplex.
T. Kyle Petersen
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A birational lifting of the Stanley-Thomas word on products of two chains [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 The dynamics of certain combinatorial actions and their liftings to actions at the piecewise-linear and birational level have been studied lately with an eye towards questions of periodicity, orbit structure, and invariants.
Michael Joseph, Tom Roby
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Haar graphical representations of finite groups and an application to poset representations [PDF]
J. Comb. Theory BLet $R$ be a group and let $S$ be a subset of $R$. The Haar graph $\mathrm{Haar}(R,S)$ of $R$ with connection set $S$ is the graph having vertex set $R\times\{-1,1\}$, where two distinct vertices $(x,-1)$ and $(y,1)$ are declared to be adjacent if and ...
Joy Morris, Pablo Spiga
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On the poset of non-attacking king permutations
European journal of combinatorics (Print), 2020 A king-non-attacking permutation is a permutation π ∈ S n such that | π i − π i − 1 | ≠ 1 for each i ∈ { 2 , … , n } . We investigate the structure of the poset of these permutations under the containment relation, and also provide some results on its ...
Eli Bagno +3 more
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Enumerative Combinatorics of Intervals in the Dyck Pattern Poset [PDF]
Order, 2019 We initiate the study of the enumerative combinatorics of the intervals in the Dyck pattern poset. More specifically, we find some closed formulas to express the size of some specific intervals, as well as the number of their covering relations.
A. Bernini +3 more
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The common basis complex and the partial decomposition poset [PDF]
For a finite-dimensional vector space $V$, the common basis complex of $V$ is the simplicial complex whose vertices are the proper non-zero subspaces of $V$, and $\sigma$ is a simplex if and only if there exists a basis $B$ of $V$ that contains a basis ...
B. Bruck, K. I. Piterman, V. Welker
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Homomesy in products of two chains [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 Many cyclic actions $τ$ on a finite set $\mathcal{S}$ ; of combinatorial objects, along with a natural statistic $f$ on $\mathcal{S}$, exhibit ``homomesy'': the average of $f$ over each $τ$-orbit in $\mathcal{S} $ is the same as the average of $f$ over ...
James Propp, Tom Roby
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Decomposition spaces and poset-stratified spaces [PDF]
, 2019 In 1920s R. L. Moore introduced \emph{upper semicontinuous} and \emph{lower semicontinuous} decompositions in studying decomposition spaces. Upper semicontinuous decompositions were studied very well by himself and later by R.H. Bing in 1950s.
Shoji Yokura
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Base Axioms of Modular Supermatroids
Journal of Applied Mathematics, 2014 This paper studies axiom systems of supermatroids. Barnabei et al.'s base axioms concerning poset matroids (i.e., distributive supermatroids) are generalized to modular supermatroids, and a mistake in the proof of base axioms of poset matroids is pointed
Xiaonan Li, Sanyang Liu
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