Regularity, depth and arithmetic rank of bipartite edge ideals
Manoj Kummini
DOI: 10.1007/s10801-009-0171-6
Abstract
We study minimal free resolutions of edge ideals of bipartite graphs. We associate a directed graph to a bipartite graph whose edge ideal is unmixed, and give expressions for the regularity and the depth of the edge ideal in terms of invariants of the directed graph. For some classes of unmixed edge ideals, we show that the arithmetic rank of the ideal equals projective dimension of its quotient.
Pages: 429–445
Keywords: keywords monomial ideals; graded free resolutions; arithmetic rank
Full Text: PDF
References
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