On binomial equations defining rational normal scrolls
نویسنده
چکیده
We show that a rational normal scroll can in general be set-theoretically defined by a proper subset of the 2-minors of the associated two-row matrix. This allows us to find a class of rational normal scrolls that are almost settheoretic complete intersections.
منابع مشابه
Binomial edge ideals and rational normal scrolls
Let $X=left( begin{array}{llll} x_1 & ldots & x_{n-1}& x_n\ x_2& ldots & x_n & x_{n+1} end{array}right)$ be the Hankel matrix of size $2times n$ and let $G$ be a closed graph on the vertex set $[n].$ We study the binomial ideal $I_Gsubset K[x_1,ldots,x_{n+1}]$ which is generated by all the $2$-minors of $X$ which correspond to the edges of $G.$ We show that $I_G$ is Cohen-Macaula...
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