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arXiv · 2210.12665

Non-simple polyominoes of Kőnig type and their canonical module

Rodica Dinu·Francesco Navarra
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Abstract

We study the Kőnig type property for non-simple polyominoes. We prove that, for closed path polyominoes, the polyomino ideals are of Kőnig type, extending the results of Herzog and Hibi for simple thin polyominoes. As an application of this result, we give a combinatorial interpretation for the canonical module of the coordinate ring of a sub-class of closed path polyominoes, namely circle closed path polyominoes. In this case, we compute also the Cohen-Macaulay type and we show that $K[\mathcal{P}]$ is a level ring.

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Rodica Dinu, Francesco Navarra. 2025-03-06. Non-simple polyominoes of Kőnig type and their canonical module. https://doi.org/10.1016/j.jalgebra.2025.02.034

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