A combinatorial interpolation between the hypercube and the associahedron

Lara Bossinger; Ömer Gürdoğan

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arXiv · 2609.38456

A combinatorial interpolation between the hypercube and the associahedron

Lara Bossinger·Ömer Gürdoğan

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Abstract

We study a family of polytopes interpolating between the hypercube and the associahedron. We give an explicit description of their normal fans and describe their combinatorics in terms of chord diagrams associated to their vertices. This yields interesting number sequences generalizing Pell numbers and asymptotic to Catalan numbers. We describe the transition between the normal fans in terms of star subdivisions and relate them to polytopes associated to Dyck paths as in [Veronica Calvo Cortes and Hadleigh Frost. Dyck paths, Configuration Spaces and Polytopes for Linear Nakayama algebras. https://arxiv.org/abs/2602.04571] and hypergraphic polytopes defined in [Carolina Benedetti, Nantel Bergeron, and John Machacek. Hypergraphic polytopes: combinatorial properties and antipode. Journal of Combinatorics. 2019]. Furthermore, all polytopes in our families yield binary geometries.

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Lara Bossinger, Ömer Gürdoğan. 2026-09-29. A combinatorial interpolation between the hypercube and the associahedron. https://arxiv.org/abs/2609.38456

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