Results 31 to 40 of about 4,538 (218)
On Finding Two Posets that Cover Given Linear Orders
Algorithms, 2019 The Poset Cover Problem is an optimization problem where the goal is to determine a minimum set of posets that covers a given set of linear orders. This problem is relevant in the field of data mining, specifically in determining directed networks or ...
Ivy Ordanel +2 more
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Sectionally Pseudocomplemented Posets [PDF]
Order, 2021 AbstractThe concept of a sectionally pseudocomplemented lattice was introduced in Birkhoff (1979) as an extension of relative pseudocomplementation for not necessarily distributive lattices. The typical example of such a lattice is the non-modular lattice N5.
Ivan Chajda, Helmut Länger, Jan Paseka
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, 2013 Let X be a finite set. This paper describes some topological and combinatorial properties of the poset \Omega_X of order relations on X. In particular, the homotopy type of all the intervals in \Omega_X is precisely determined, and the Möbius function of \Omega_X is computed.
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Poset limits and exchangeable random posets [PDF]
Combinatorica, 2011 36 ...
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The topology of the permutation pattern poset [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 The set of all permutations, ordered by pattern containment, forms a poset. This extended abstract presents the first explicit major results on the topology of intervals in this poset.
Peter McNamara, Einar Steingrımsson
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The poset of mesh patterns [PDF]
, 2020 We introduce the poset of mesh patterns, which generalises the permutation pattern poset. We fully classify the mesh patterns for which the interval [1∅, m] is non-pure, where 1∅ is the unshaded singleton mesh pattern.
Ulfarsson, H, Smith, JP
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Intuitionistic-like unsharp implication and negation defined on a poset [PDF]
Mathematica BohemicaThe aim of the present paper is to show that the concepts of the intuitionistic implication and negation formalized by means of a Heyting algebra can be generalized in such a way that these concepts are formalized by means of a bounded poset.
Ivan Chajda, Helmut Länger
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Journal of Combinatorics, 2019 Let $G$ be an acylic directed graph. For each vertex $g \in G$, we define an involution on the independent sets of $G$. We call these involutions flips, and use them to define a new partial order on independent sets of $G$. Trim lattices generalize distributive lattices by removing the graded hypothesis: a graded trim lattice is a distributive lattice,
Thomas, Hugh, Williams, Nathan
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The Möbius function of separable and decomposable permutations
, 2011 We give a recursive formula for the Moebius function of an interval $[\sigma,\pi]$ in the poset of permutations ordered by pattern containment in the case where $\pi$ is a decomposable permutation, that is, consists of two blocks where the first one ...
Jelínek, Vít +7 more
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The Journal of Symbolic Logic, 2009 AbstractHirschfeldt and Shore have introduced a notion of stability for infinite posets. We define an arguably more natural notion called weak stability, and we study the existence of infinite computable or low chains or antichains, and of infinite chains and antichains, in infinite computable stable and weakly stable posets.
Jockusch, Jr., Carl G. +4 more
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