Partition and Cohen–Macaulay extenders
نویسندگان
چکیده
If a pure simplicial complex is partitionable, then its h-vector has combinatorial interpretation in terms of any partitioning the complex. Given non-partitionable Δ, we construct Γ⊇Δ same dimension such that both Γ and relative (Γ,Δ) are partitionable. This allows us to rewrite as difference two h-vectors partitionable complexes, giving an analogous By contrast, for given Δ it not always possible find Cohen–Macaulay. We characterize when this possible, show construction case remarkably straightforward. end with note on similar notion shellability connection Simon’s conjecture extendable uniform matroids.
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2022
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2021.103488