Results 1 to 10 of about 125 (45)
EL-Shellability of Generalized Noncrossing Partitions [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 In this article we prove that the poset of m-divisible noncrossing partitions is EL-shellable for every well-generated complex reflection group. This was an open problem for type G(d,d,n) and for the exceptional types, for which a proof is given case-by ...
Henri Mühle
doaj +8 more sources
On the Topology of the Cambrian Semilattices [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 For an arbitrary Coxeter group $W$, David Speyer and Nathan Reading defined Cambrian semilattices $C_{\gamma}$ as certain sub-semilattices of the weak order on $W$.
Myrto Kallipoliti, Henri Mühle
doaj +7 more sources
The Bruhat order on conjugation-invariant sets of involutions in the symmetric group [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 12 pages, 3 ...
Mikael Hansson
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Shellability of generalized Dowling posets [PDF]
Journal of Combinatorial Theory - Series A, 2020 A generalization of Dowling lattices was recently introduced by Bibby and Gadish, in a work on orbit configuration spaces. The authors left open the question as to whether these posets are shellable.
Giovanni Paolini
exaly +3 more sources
On Bruhat posets associated to compositions [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 The purpose of this work is to initiate a combinatorial study of the Bruhat-Chevalley ordering on certain sets of permutations obtained by omitting the parentheses from their standard cyclic notation.
Mahir Bilen Can, Yonah Cherniavsky
doaj +1 more source
On the (co)homology of the poset of weighted partitions [PDF]
, 2015 We consider the poset of weighted partitions $\Pi_n^w$, introduced by Dotsenko and Khoroshkin in their study of a certain pair of dual operads. The maximal intervals of $\Pi_n^w$ provide a generalization of the lattice $\Pi_n$ of partitions, which we ...
D'León, Rafael S. González +1 more
core +1 more source
The structure of the consecutive pattern poset [PDF]
, 2017 The consecutive pattern poset is the infinite partially ordered set of all permutations where $\sigma\le\tau$ if $\tau$ has a subsequence of adjacent entries in the same relative order as the entries of $\sigma$.
Peter, R. W. Mcnamara, Sergi Elizalde
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Segre Powers of Posets Preserve EL-Shellability
Order9 pages, 3 figures. This paper contains the results of Section 2, Theorems 2.6 and 2.7 of arXiv2408.08421v2 (Version 2), which was was split into two parts. The main part (25 pages) has already appeared in the journal Enumer. Comb. Appl. 5 (2025), no. 3, Paper No. S2R19, 21 pp., doi.org/10.54550/ECA2025V5S3R19.
Li, Yifei, Sundaram, Sheila
openaire +2 more sources
The absolute order on the hyperoctahedral group [PDF]
, 2009 The absolute order on the hyperoctahedral group $B_n$ is investigated. It is proved that the order ideal of this poset generated by the Coxeter elements is homotopy Cohen-Macaulay and the M\"obius number of this ideal is computed.
Kallipoliti, Myrto
core +5 more sources
On the shard intersection order of a Coxeter group
, 2013 Introduced by Reading, the shard intersection order of a finite Coxeter group $W$ is a lattice structure on the elements of $W$ that contains the poset of noncrossing partitions $NC(W)$ as a sublattice.
Petersen, T. Kyle
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