DM 2011 | Sciweavers

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DM
2011

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A combinatorial approach to height sequences in finite partially ordered sets

12 years 11 months ago

Fix an element x of a ﬁnite partially ordered set P on n elements. Then let hi(x) be the number of linear extensions of P in which x is in position i, counting from the bottom. T...

Csaba Biró, William T. Trotter

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DM
2011

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Singletons and adjacencies of set partitions of type B

12 years 11 months ago

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We show that the joint distribution of the number of singleton pairs and the number of adjacency pairs is symmetric over the set partitions of type Bn without zero-block, in analo...

William Y. C. Chen, David G. L. Wang

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DM
2011

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Loose Hamilton cycles in hypergraphs

12 years 11 months ago

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We prove that any k-uniform hypergraph on n vertices with minimum degree at least n 2(k−1) + o(n) contains a loose Hamilton cycle. The proof strategy is similar to that used by K...

Peter Keevash, Daniela Kühn, Richard Mycroft,...

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DM
2011

253views Education» more DM 2011»

On the hyperbolicity constant in graphs

12 years 11 months ago

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If X is a geodesic metric space and x1, x2, x3 ∈ X, a geodesic triangle T = {x1, x2, x3} is the union of the three geodesics [x1x2], [x2x3] and [x3x1] in X. The space X is δ-hy...

José M. Rodríguez, Jose Maria Sigarr...

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DM
2011

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Hall-Littlewood polynomials, alcove walks, and fillings of Young diagrams

12 years 11 months ago