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arXiv · 2405.05812

The $cd$-index of semi-Eulerian posets

Martina Juhnke-Kubitzke·José Alejandro Samper·Lorenzo Venturello
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Abstract

We generalize the definition of the $cd$-index of an Eulerian poset to the class of semi-Eulerian posets. For simplicial semi-Eulerian Buchsbaum posets, we show that all coefficients of the $cd$-index are non-negative. This proves a conjecture of Novik for odd dimensional manifolds and extends it to the even dimensional case.

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Martina Juhnke-Kubitzke, José Alejandro Samper, Lorenzo Venturello. 2024-05-09. The $cd$-index of semi-Eulerian posets. https://arxiv.org/abs/2405.05812

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