Edgewise Cohen-Macaulay connectivity of partially ordered sets

  title={Edgewise Cohen-Macaulay connectivity of partially ordered sets},
  author={Christos A. Athanasiadis and Myrto Kallipoliti},
  journal={arXiv: Combinatorics},
The proper parts of face lattices of convex polytopes are shown to satisfy a strong form of the Cohen--Macaulay property, namely that removing from their Hasse diagram all edges in any closed interval results in a Cohen--Macaulay poset of the same rank. A corresponding notion of edgewise Cohen--Macaulay connectivity for partially ordered sets is investigated. Examples and open questions are discussed. 

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