Results 11 to 20 of about 619 (166)
Soft comput, 2021 AbstractWe introduce so-called consistent posets which are bounded posets with an antitone involution$$'$$′where the lower cones of$$x,x'$$x,x′and of$$y,y'$$y,y′coincide provided thatx, yare different from 0, 1 and, moreover, ifx, yare different from 0, then their lower cone is different from 0, too.
Chajda I, Länger H.
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Journal of Combinatorial Theory, Series A, 2021 In 1995 Stanley introduced the chromatic symmetric function $X_G$ of a graph $G$, whose $e$-positivity and Schur-positivity has been of large interest. In this paper we study the relative $e$-positivity and Schur-positivity between connected graphs on $n$ vertices.
Dahlberg, Samantha +2 more
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Mediterranean Journal of Mathematics, 2020 We introduce Cayley posets as posets arising naturally from pairs ...
Ignacio García-Marco +2 more
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Israel Journal of Mathematics, 2020 New references are added, several typos are ...
Can, Mahir Bilen, Cherniavsky, Yonah
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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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Open Mathematics, 2006 AbstractThis article extends a paper of Abraham and Bonnet which generalised the famous Hausdorff characterisation of the class of scattered linear orders. They gave an inductively defined hierarchy that characterised the class of scattered posets which do not have infinite incomparability antichains (i.e. have the FAC).
Džamonja Mirna, Thompson Katherine
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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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The coefficients of transitivity of the posets of MM-type being the highest supercritical poset
Науковий вісник Ужгородського університету. Серія: Математика і інформатика, 2022 The representations of partially ordered sets (abbreviated as posets), introduced by L. A. Nazarova and A. V. Roiter (in matrix form) in 1972, play an important role in the modern representation theory. In his first paper on this topic M. M.
В. М. Бондаренко +2 more
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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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Journal of High Energy Physics, 2014 The non-Abelian exponentiation theorem has recently been generalised to correlators of multiple Wilson line operators. The perturbative expansions of these correlators exponentiate in terms of sets of diagrams called webs, which together give rise to colour factors corresponding to connected graphs.
Dukes, M. +4 more
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