Binomial edge ideals and rational normal scrolls
نویسندگان
چکیده مقاله:
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-Macaulay. We find the minimal primes of $I_G$ and show that $I_G$ is a set theoretical complete intersection. Moreover, a sharp upper bound for the regularity of $I_G$ is given.
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...
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عنوان ژورنال
دوره 41 شماره 4
صفحات 971- 979
تاریخ انتشار 2015-08-01
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