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arXiv 2303.02791math.ACmath.CO
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关于边理想符号幂的无平方部分的正则性

On the Regularity of squarefree part of symbolic powers of edge ideals

S. A. Seyed Fakhari

摘要:

假设$G$是一个具有边理想$I(G)$的图。对于每一个整数$s\geq 1$,我们用$I(G)^{\{s\}}$表示$I(G)$的$s$次符号幂的无平方部分。当$G$是弦图时,我们确定了$I(G)^{\{s\}}$正则性的一个上界.如果$G$是Cameron-Walker图,我们用$G$的导出匹配数来计算${\rm reg}(I(G)^{\{s\}}$.此外,对于任何图$G$,我们提供了尖锐上界为${\rm reg}(I(G)^{\{2\}})$和${\rm reg}(I(G)^{\{3\}})$。

英文摘要:

Assume that $G$ is a graph with edge ideal $I(G)$. For every integer $s\geq 1$, we denote the squarefree part of the $s$-th symbolic power of $I(G)$ by $I(G)^{\{s\}}$. We determine an upper bound for the regularity of $I(G)^{\{s\}}$ when $G$ is a chordal graph. If $G$ is a Cameron-Walker graphs, we compute ${\rm reg}(I(G)^{\{s\}}$ in terms of the induced matching number of $G$. Moreover, for any graph $G$, we provide sharp upper bounds for ${\rm reg}(I(G)^{\{2\}})$ and ${\rm reg}(I(G)^{\{3\}})$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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