Arithmetical rank of squarefree monomial ideals generated by five elements or with arithmetic degree four

Kyouko Kimura; Giancarlo Rinaldo; Naoki Terai

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arXiv · 1107.0563

Arithmetical rank of squarefree monomial ideals generated by five elements or with arithmetic degree four

Kyouko Kimura·Giancarlo Rinaldo·Naoki Terai

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Abstract

Let $I$ be a squarefree monomial ideal of a polynomial ring $S$. In this paper, we prove that the arithmetical rank of $I$ is equal to the projective dimension of $S/I$ when one of the following conditions is satisfied: (1) $\mu (I) \leq 5$; (2) $\arithdeg I \leq 4$.

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Kyouko Kimura, Giancarlo Rinaldo, Naoki Terai. 2011-07-04. Arithmetical rank of squarefree monomial ideals generated by five elements or with arithmetic degree four. https://arxiv.org/abs/1107.0563

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