Results 41 to 50 of about 21,654,511 (186)
The Whitney duals of a graded poset [PDF]
Journal of Combinatorial Theory, 2018 We introduce the notion of a \emph{Whitney dual} of a graded poset. Two posets are Whitney duals to each other if (the absolute value of) their Whitney numbers of the first and second kind are interchanged between the two posets.
Rafael S. Gonz'alez D'Le'on +1 more
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Maximal 0-1-fillings of moon polyominoes with restricted chain lengths and rc-graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2011 We show that maximal 0-1-fillings of moon polynomials, with restricted chain lengths, can be identified with certain rc-graphs, also known as pipe dreams.
Martin Rubey
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Laplacian immanantal polynomials and the GTS poset on trees [PDF]
Linear Algebra and its Applications, 2017 Let T be a tree on n vertices with Laplacian L T and let GTS n be the generalised tree shift poset on the set of unlabelled trees on n vertices. Inequalities are known for coefficients of the characteristic polynomial of L T as we go up the poset GTS n .
M. Nagar, S. Sivasubramanian
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Posets Arising as 1-Skeleta of Simple Polytopes, the Nonrevisiting Path Conjecture, and Poset Topology [PDF]
Discrete & Computational Geometry, 2018 Given any polytope P and any generic linear functional c\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength ...
P. Hersh
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Poset-stratified space structures of homotopy sets [PDF]
Homology, Homotopy and Applications, 2018 A poset-stratified space is a pair $(S, S \xrightarrow \pi P)$ of a topological space $S$ and a continuous map $\pi: S \to P$ with a poset $P$ considered as a topological space with its associated Alexandroff topology.
Toshihiro Yamaguchi, Shoji Yokura
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The topology of restricted partition posets [PDF]
Discrete Mathematics & Theoretical Computer Science, 2011 For each composition $\vec{c}$ we show that the order complex of the poset of pointed set partitions $Π ^• _{\vec{c}}$ is a wedge of $β\vec{c}$ spheres of the same dimensions, where $β\vec{c}$ is the number of permutations with descent composition ^$\vec{
Richard Ehrenborg, JiYoon Jung
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Enumerative Results on the Schröder Pattern Poset [PDF]
International Workshop on Cellular Automata and Discrete Complex Systems, 2017 The set of Schroder words (Schroder language) is endowed with a natural partial order, which can be conveniently described by interpreting Schroder words as lattice paths. The resulting poset is called the Schroder pattern poset.
Lapo Cioni, L. Ferrari
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Forbidding Rank-Preserving Copies of a Poset [PDF]
Order, 2017 The maximum size, La(n,P), of a family of subsets of [n] = {1,2,...,n} without containing a copy of P as a subposet, has been extensively studied. Let P be a graded poset.
Dániel Gerbner +4 more
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How to get the weak order out of a digraph ? [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 We construct a poset from a simple acyclic digraph together with a valuation on its vertices, and we compute the values of its Möbius function. We show that the weak order on Coxeter groups $A$$n-1$, $B$$n$, $Ã$$n$, and the flag weak order on the wreath ...
Francois Viard
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A particular poset and some special types of functions on BE-algebras
, 2020 BCK and BCI algebras were introduced by K. Iseki in 1966. After the introduction of these two types of algebras many more systems of similar type were introduced, discussed and studied by so many authors in the last twenty years.
K. Pathak, P. Sabhapandit
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