Packing and Covering Immersions in 4-Edge-Connected Graphs
arXiv:1505.00867 · doi:10.1016/j.jctb.2021.06.005
Abstract
A graph contains another graph as an immersion if can be obtained from a subgraph of by splitting off edges and removing isolated vertices. In this paper, we prove an edge-variant of the Erdős-Pósa property with respect to the immersion containment in 4-edge-connected graphs. More precisely, we prove that for every graph , there exists a function such that for every 4-edge-connected graph , either contains pairwise edge-disjoint subgraphs each containing as an immersion, or there exists a set of at most edges of 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.