Results 41 to 50 of about 4,538 (218)
Pattern-avoiding Dyck paths [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 We introduce the notion of $\textit{pattern}$ in the context of lattice paths, and investigate it in the specific case of Dyck paths. Similarly to the case of permutations, the pattern-containment relation defines a poset structure on the set of all Dyck
Antonio Bernini +3 more
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European Journal of Combinatorics, 2011 AmS-LaTeX, 36 pages; references added, discussion of the Babson-Hersh result in Section 3 ...
Hetyei, Gábor, Krattenthaler, Christian
openaire +4 more sources
A Min–Max Relation on Dicuts and Dijoins in Weighted Chordal Digraphs
Journal of Graph Theory, EarlyView.ABSTRACT In a digraph, a dicut is a cut where all the arcs cross in one direction. A dijoin is a subset of arcs that intersects every dicut. Edmonds and Giles conjectured that in a weighted digraph, the minimum weight of a dicut is equal to the maximum size of a packing of dijoins. This has been disproved. However, the unweighted version conjectured by
Gérard Cornuéjols, Siyue Liu, R. Ravi
wiley +1 more source
The Equivalence of Two Modes of Order Convergence
MathematicsIt is well known that if a poset satisfies Property A and its dual form, then the o-convergence and o2-convergence in the poset are equivalent. In this paper, we supply an example to illustrate that a poset in which the o-convergence and o2-convergence ...
Tao Sun, Nianbai Fan
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Base Axioms of Modular Supermatroids
Journal of Applied Mathematics, 2014 This paper studies axiom systems of supermatroids. Barnabei et al.'s base axioms concerning poset matroids (i.e., distributive supermatroids) are generalized to modular supermatroids, and a mistake in the proof of base axioms of poset matroids is pointed
Xiaonan Li, Sanyang Liu
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Reduced zero-divisor graphs of posets [PDF]
Transactions on Combinatorics, 2018 This paper investigates properties of the reduced zero-divisor graph of a poset. We show that a vertex is an annihilator prime ideal if and only if it is adjacent to all other annihilator prime ideals and there are always two annihilator prime ideals ...
Deiborlang Nongsiang, Promode Saikia
doaj +1 more source
SIAM Journal on Discrete Mathematics, 2023 36 pages, 1 figure. Added a reference to Daykin--Daykin--Paterson inequality that were previously presented as Conjecture 4.19 in ...
Swee Hong Chan, Igor Pak, Greta Panova
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Climate Change and (Mal)Adaptation in Tourism‐Intensive Alpine Regions
The Political Quarterly, EarlyView.Abstract Tourism, especially in winter, accounts for a large share of economic income in Alpine regions. At the same time, these regions are more severely affected by climate change, leading to shorter winter seasons and reduced snow cover. This presents a pressing issue for areas reliant on income from winter tourism through activities such as skiing.
Valentina Ausserladscheider
wiley +1 more source
An example Ginsburg said in 1984 he was "unable to find" and a forbidden subposet characterization of subsets of regular posets [PDF]
Mathematica BohemicaIn 1984, Ginsburg wrote, "We have been unable to find an example of an ordered set $P$ having the properties of [being complete, densely ordered, with no antichain other than $\{0\}$ and $\{1\}$ that is a cutset] and in which all antichains are countable.
Jonathan David Farley
doaj +1 more source
Building Emerging Images with Tiled Orders and Posets
Mathematics, 2021 We introduce an algorithm based on posets and tiled orders to generate emerging images. Experimental results allow concluding that images obtained with these kinds of tools are easy to detect by human beings.
María Alejandra Osorio Angarita +2 more
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