Results 21 to 30 of about 462 (185)
Mediterranean Journal of Mathematics, 2020 We introduce Cayley posets as posets arising naturally from pairs ...
García-Marco, Ignacio +2 more
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The Electronic Journal of Combinatorics, 2019 We define a family of combinatorial objects, which we call Baxter posets. We prove that Baxter posets are counted by the Baxter numbers by showing that they are the adjacency posets of diagonal rectangulations. Given a diagonal rectangulation, we describe the cover relations in the associated Baxter poset.
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Morita theorems for partially ordered monoids; pp. 221–237 [PDF]
Proceedings of the Estonian Academy of Sciences, 2011 Two partially ordered monoids S and T are called Morita equivalent if the categories of right S-posets and right T-posets are Pos-equivalent as categories enriched over the category Pos of posets.
Valdis Laan
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Discrete & Computational Geometry, 2004 Given a locally finite partially ordered set \(Q\), a second poset \(T(Q)\) is described. When \(Q\) is an Eulerian poset, often the same is true of \(T(Q)\). The main objects of study, the finite Eulerian posets \(T_n\) (for \(n = 1, 2, \ldots\)), are then obtained as intervals in the Eulerian poset \(T(P)\), where \(P\) is a certain relatively simple
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Poset binomials and rainbow characters [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 This paper introduces a variation on the binomial coefficient that depends on a poset and interpolates between $q$-binomials and 1-binomials: a total order gives the usual $q$-binomial, and a poset with no relations gives the usual binomial coefficient ...
Daniel Bragg, Nathaniel Thiem
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Enumeration of Graded (3 + 1)-Avoiding Posets [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 The notion of (3+1)-avoidance appears in many places in enumerative combinatorics, but the natural goal of enumerating all (3+1)-avoiding posets remains open. In this paper, we enumerate \emphgraded (3+1)-avoiding posets.
Joel Lewis Brewster, Yan X Zhang
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On the poset of all posets on n elements
Discrete Applied Mathematics, 1994 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Richard A. Brualdi +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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The method of double chains for largest families with excluded subposets
Electronic Journal of Graph Theory and Applications, 2013 For a given finite poset $P$, $La(n,P)$ denotes the largest size of a family $\mathcal{F}$ of subsets of $[n]$ not containing $P$ as a weak subposet. We exactly determine $La(n,P)$ for infinitely many $P$ posets.
Peter Burcsi, Daniel T. Nagy
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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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