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arXiv · 1703.03357

An algorithm to compute a presentation of pushforward modules

M. E. Hernandes·A. J. Miranda·G. Peñafort-Sanchis
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Abstract

We describe an algorithm to compute a presentation of the pushforward module $f_*{\mathcal O}_{\mathcal{X}}$ for a finite map germ $f\colon \mathcal{X}\to ({\mathbb{C}}^{n+1},0)$, where $\mathcal{X}$ is Cohen-Macaulay of dimension $n$. The algorithm is an improvement of a method by Mond and Pellikaan. We give applications to problems in singularity theory, computed by means of an implementation in the software Singular.

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M. E. Hernandes, A. J. Miranda, G. Peñafort-Sanchis. 2017-03-09. An algorithm to compute a presentation of pushforward modules. https://arxiv.org/abs/1703.03357

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