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arXiv · 1504.01520

Alexander duality for monomial ideals associated with isotone maps between posets

Juergen Herzog·Ayesha Asloob Qureshi·Akihiro Shikama
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Abstract

For a pair $(P,Q)$ of finite posets the generators of the ideal $L(P,Q)$ correspond bijectively to the isotone maps from $P$ to $Q$. In this note we determine all pairs $(P,Q)$ for which the Alexander dual of $L(P,Q)$ coincides with $L(Q,P)$, up to a switch of the indices.

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Juergen Herzog, Ayesha Asloob Qureshi, Akihiro Shikama. 2015-04-07. Alexander duality for monomial ideals associated with isotone maps between posets. https://arxiv.org/abs/1504.01520

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