## Journal of Commutative Algebra

### Postulation and reduction vectors of multigraded filtrations of ideals

#### Abstract

We study the relationship between postulation and reduction vectors of admissible multigraded filtrations $\mathcal{F}= \{\mathcal{F} (\underline{n})\}_{\underline{n} \in \mathbb{Z} ^s}$ of ideals in Cohen-Macaulay local rings of dimension at most two. This is enabled by a suitable generalization of the Kirby-Mehran complex. An analysis of its homology leads to an analogue of Huneke's fundamental lemma which plays a crucial role in our investigations. We also clarify the relationship between the Cohen-Macaulay property of the multigraded Rees algebra of $\mathcal{F}$ and reduction vectors with respect to complete reductions of $\mathcal{F}$.

#### Article information

Source
J. Commut. Algebra, Volume 9, Number 4 (2017), 563-597.

Dates
First available in Project Euclid: 14 October 2017

https://projecteuclid.org/euclid.jca/1507946699

Digital Object Identifier
doi:10.1216/JCA-2017-9-4-563

Mathematical Reviews number (MathSciNet)
MR3713528

Zentralblatt MATH identifier
06797099

#### Citation

Sarkar, Parangama; Verma, J.K. Postulation and reduction vectors of multigraded filtrations of ideals. J. Commut. Algebra 9 (2017), no. 4, 563--597. doi:10.1216/JCA-2017-9-4-563. https://projecteuclid.org/euclid.jca/1507946699

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