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arXiv · 1505.00867

Packing and Covering Immersions in 4-Edge-Connected Graphs

Chun-Hung Liu
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Abstract

A graph $G$ contains another graph $H$ as an immersion if $H$ can be obtained from a subgraph of $G$ by splitting off edges and removing isolated vertices. In this paper, we prove an edge-variant of the Erd\H{o}s-P\'{o}sa property with respect to the immersion containment in 4-edge-connected graphs. More precisely, we prove that for every graph $H$, there exists a function $f$ such that for every 4-edge-connected graph $G$, either $G$ contains $k$ pairwise edge-disjoint subgraphs each containing $H$ as an immersion, or there exists a set of at most $f(k)$ edges of $G$ intersecting all such subgraphs. This theorem is best possible in the sense that the 4-edge-connectivity cannot be replaced by the 3-edge-connectivity.

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Chun-Hung Liu. 2015-05-05. Packing and Covering Immersions in 4-Edge-Connected Graphs. https://doi.org/10.1016/j.jctb.2021.06.005

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