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arXiv · 2112.02539

Motzkin combinatorics in linear degenerations of the flag variety

Giovanni Cerulli Irelli·Francesco Esposito·Mario Marietti
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Abstract

We establish an explicit combinatorial/homological characterization of supports for linear degenerations of flag varieties. For such purpose, we introduce the concept of an excessive multisegment. It provides a new class of combinatorial objects counted by Motzkin numbers.

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Giovanni Cerulli Irelli, Francesco Esposito, Mario Marietti. 2021-12-05. Motzkin combinatorics in linear degenerations of the flag variety. https://arxiv.org/abs/2112.02539

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