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arXiv · 2407.12400

Stellar subdivisions, wedges and Buchstaber numbers

Suyoung Choi·Hyeontae Jang
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Abstract

A seed is a PL sphere that is not obtainable by a wedge operation from any other PL sphere. In this paper, we study two operations on PL spheres, known as the stellar subdivision and the wedge, that preserve the maximality of Buchstaber numbers and polytopality. We construct a new polytopal toric colorable seed from these two operations. As a corollary, we prove that the toric colorable seed inequality established by Choi and Park is tight.

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Suyoung Choi, Hyeontae Jang. 2024-07-17. Stellar subdivisions, wedges and Buchstaber numbers. https://doi.org/10.2140/agt.2026.26.751

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