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arXiv · 2506.13684

Sums of Schubert structure constants with bounded Coxeter length

Ada Stelzer
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Abstract

Pak-Robichaux recently introduced a signed puzzle rule for Schubert structure constants, which they use to show that sums $γ_k(n)$ of these constants with a bounded number of inversions are polynomial. We give a different, conceptual proof of their theorem. Our argument computes the lead term of $γ_k(n)$ and extends to all classical Lie types.

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Ada Stelzer. 2025-06-16. Sums of Schubert structure constants with bounded Coxeter length. https://arxiv.org/abs/2506.13684

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