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arXiv · 1007.1911

Catalan lattices on series parallel interval orders

Filippo Disanto·Luca Ferrari·Renzo Pinzani·Simone Rinaldi
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Abstract

Using the notion of series parallel interval order, we propose a unified setting to describe Dyck lattices and Tamari lattices (two well known lattice structures on Catalan objects) in terms of basic notions of the theory of posets. As a consequence of our approach, we find an extremely simple proof of the fact that the Dyck order is a refinement of the Tamari one. Moreover, we provide a description of both the weak and the strong Bruhat order on 312-avoiding permutations, by recovering the proof of the fact that they are isomorphic to the Tamari and the Dyck order, respectively; our proof, which simplifies the existing ones, relies on our results on series parallel interval orders.

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Filippo Disanto, Luca Ferrari, Renzo Pinzani, Simone Rinaldi. 2010-07-12. Catalan lattices on series parallel interval orders. https://arxiv.org/abs/1007.1911

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