Forced perimeter in Elnitksy polygons

Bridget Eileen Tenner

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arXiv · 2008.05347

Forced perimeter in Elnitksy polygons

Bridget Eileen Tenner

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Abstract

We study tiling-based perimeter and characterize when a given perimeter tile appears in all rhombic tilings of an Elnitsky polygon. Regardless of where on the perimeter this tile appears, its forcing can be described in terms of 321-patterns. We characterize the permutations with maximally many forced right-perimeter tiles, and show that they are enumerated by the Catalan numbers.

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Bridget Eileen Tenner. 2020-08-12. Forced perimeter in Elnitksy polygons. https://arxiv.org/abs/2008.05347

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