Edgewise Cohen-Macaulay connectivity of partially ordered sets
DOI:
https://doi.org/10.7146/math.scand.a-97270Abstract
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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