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arXiv · 1212.4358

Bounds for the Betti numbers of successive stellar subdivisions of a simplex

Janko Boehm·Stavros Argyrios Papadakis
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Abstract

We give a bound for the Betti numbers of the Stanley-Reisner ring of a stellar subdivision of a Gorenstein* simplicial complex by applying unprojection theory. From this we derive a bound for the Betti numbers of iterated stellar subdivisions of the boundary complex of a simplex. The bound depends only on the number of subdivisions, and we construct examples which prove that it is sharp.

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Janko Boehm, Stavros Argyrios Papadakis. 2012-12-18. Bounds for the Betti numbers of successive stellar subdivisions of a simplex. https://arxiv.org/abs/1212.4358

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