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关于带多重阿贝尔群标签的图中循环的统一埃尔多斯-波萨定理

A unified Erdős-Pósa theorem for cycles in graphs labelled by multiple abelian groups

University of Primorska(普里莫斯卡大学);Monash University(蒙纳士大学);Institute for Basic Science (IBS)(基础科学研究院);Hanyang University(汉阳大学)

J. Pascal Gollin, Kevin Hendrey, O-joung Kwon, Sang-il Oum, Youngho Yoo

AI总结:

本文统一了图中多种循环的埃尔多斯-波萨定理,并扩展到带多重阿贝尔群标签的图中,提供了新的结果和障碍特征化。

摘要:

1965年,埃尔多斯和波萨证明了图中循环包的大小与能击中所有循环的顶点集大小之间存在(近似)对偶性。这种对偶性不适用于奇数长度的循环,德杰特和内曼-拉拉于1988年提出寻找所有整数对$(\ell, z)$,使得对于长度为$\ell$模$z$的循环家族,这种对偶性成立。我们确定了所有这样的对数对,并进一步将这种特征推广到带有受限数量阿贝尔群标签的图中的循环,其值避开每个群的有限个元素。这几乎统一了所有已知的允许此类对偶性的循环类型,并提供了新的结果。此外,我们确定了在这种情况下实现此类对偶性的障碍,从而获得了图可嵌入固定紧致定向表面的循环的相应特征化。

英文摘要:

In 1965, Erdős and Pósa proved that there is an (approximate) duality between the maximum size of a packing of cycles and the minimum size of a vertex set hitting all cycles. Such a duality does not hold for odd cycles, and Dejter and Neumann-Lara asked in 1988 to find all pairs ${(\ell, z)}$ of integers where such a duality holds for the family of cycles of length $\ell$ modulo $z$. We characterise all such pairs, and we further generalise this characterisation to cycles in graphs labelled with a bounded number of abelian groups, whose values avoid a bounded number of elements of each group. This unifies almost all known types of cycles that admit such a duality, and it also provides new results. Moreover, we characterise the obstructions to such a duality in this setting, and thereby obtain an analogous characterisation for cycles in graphs embeddable on a fixed compact orientable surface.

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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