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arXiv · 2103.07294

Non-ambiguous trees: new results and generalisation (Full version)

Bérénice Delcroix-Oger·Florent Hivert·Patxi Laborde-Zubieta·Jean-Christophe Aval·Adrien Boussicault
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Abstract

We present a new definition of non-ambiguous trees (NATs) as labelled binary trees. We thus get a differential equation whose solution can be described combinatorially. This yields a new formula for the number of NATs. We also obtain q-versions of our formula. We finally generalise NATs to higher dimension.

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Bérénice Delcroix-Oger, Florent Hivert, Patxi Laborde-Zubieta, Jean-Christophe Aval, Adrien Boussicault. 2021-03-12. Non-ambiguous trees: new results and generalisation (Full version). https://arxiv.org/abs/2103.07294

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