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arXiv · 2511.10812

Sparse Paving Positroids

John Machacek·George D. Nasr
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Abstract

Using Postnikov's Le-diagrams, decorated permutations, and Grassmann necklaces, we classify which positroids are sparse paving matroids. This allows us to enumerate sparse paving positroids, making connections to a known sequence involving the golden ratio and to the Lucas numbers.

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John Machacek, George D. Nasr. 2025-11-13. Sparse Paving Positroids. https://doi.org/10.63151/amjc.v5i.42

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