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arXiv · 2308.05099

Inversion and Cubic Vectors for Permutrees

Daniel Tamayo Jiménez
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Abstract

We introduce two generalizations of bracket vectors from binary trees to permutrees. These new vectors help describe algebraic and geometric properties of the rotation lattice of permutrees defined by Pilaud and Pons. The first generalization serves the role of an inversion vector for permutrees allowing us to define an explicit meet operation and provide a new constructive proof of the lattice property for permutree rotation lattices. The second generalization, which we call cubic vectors, allows for the construction of a cubic realization of these lattices which is proven to form a cubical embedding of the corresponding permutreehedra. These results specialize to those known about permutahedra and associahedra.

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Daniel Tamayo Jiménez. 2023-08-09. Inversion and Cubic Vectors for Permutrees. https://arxiv.org/abs/2308.05099

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