Veronesean Almost Binomial Almost Complete Intersections
نویسندگان
چکیده
The second Veronese ideal In contains a natural complete intersection Jn generated by the principal 2-minors of a symmetric (n× n)-matrix. We determine subintersections of the primary decomposition of Jn where one intersectand is omitted. If In is omitted, the result is the other end of a complete intersection link as in liaison theory. These subintersections also yield interesting insights into binomial ideals and multigraded algebra. For example, if n is even, In is a Gorenstein ideal and the intersection of the remaining primary components of Jn equals Jn+ 〈f〉 for an explicit polynomial f constructed from the fibers of the Veronese grading map.
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