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The regularity of points in multi-projective spaces

Huy Tai Ha·Adam Van Tuyl
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Abstract

Let I = p_1^{m_1} \cap ... \cap p_s^{m_s} be the defining ideal of a scheme of fat points in P^{n_1} x ... x P^{n_k} with support in generic position. When all the m_i's are 1, we explicitly calculate the Castelnuovo-Mumford regularity of I. In general, if at least one m_i >= 2, we give an upper bound for the regularity of I, which extends the result of Catalisano, Trung and Valla to the multi-projective case.

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Huy Tai Ha, Adam Van Tuyl. 2003-07-09. The regularity of points in multi-projective spaces. https://arxiv.org/abs/math/0211263

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