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arXiv · 1409.5569

Quasi-Stable ideals and Borel-fixed ideals with a given Hilbert Polynomial

Cristina Bertone
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Abstract

The present paper investigates properties of quasi-stable ideals and of Borel-fixed ideals in a polynomial ring $k[x_0,\dots,x_n]$, in order to design two algorithms: the first one takes as input $n$ and an admissible Hilbert polynomial $P(z)$, and outputs the complete list of saturated quasi-stable ideals in the chosen polynomial ring with the given Hilbert polynomial. The second algorithm has an extra input, the characteristic of the field $k$, and outputs the complete list of saturated Borel-fixed ideals in $k[x_0,\dots,x_n]$ with Hilbert polynomial $P(z)$. The key tool for the proof of both algorithms is the combinatorial structure of a quasi-stable ideal, in particular we use a special set of generators for the considered ideals, the Pommaret basis.

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Cristina Bertone. 2014-09-19. Quasi-Stable ideals and Borel-fixed ideals with a given Hilbert Polynomial. https://arxiv.org/abs/1409.5569

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