Regularity, depth and arithmetic rank of bipartite edge ideals
نویسندگان
چکیده
منابع مشابه
Regularity, Depth and Arithmetic Rank of Bipartite Edge Ideals
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.
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ژورنال
عنوان ژورنال: Journal of Algebraic Combinatorics
سال: 2009
ISSN: 0925-9899,1572-9192
DOI: 10.1007/s10801-009-0171-6