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arXiv · 2306.04151

Group connectivity of 3-edge-connected signed graphs

Alejandra Brewer Castano·Jessica McDonald·Kathryn Nurse
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Abstract

Jaeger, Linial, Payan, and Tarsi introduced the notion of $A$-connectivity for graphs in 1992, and proved a decomposition for cubic graphs from which $A$-connectivity follows for all 3-edge-connected graphs when $|A|\geq 6$. The concept of $A$-connectivity was generalized to signed graphs by Li, Luo, Ma, and Zhang in 2018 and they proved that all 4-edge-connected flow-admissible signed graphs are $A$-connected when $|A|\geq 4$ and $|A|\neq 5$. We prove that all 3-edge-connected flow-admissible signed graphs are $A$-connected when $|A|\geq 6$ and $|A|\neq 7$. Our proof is based on a decomposition that is a signed-graph analogue of the decomposition found by Jaeger et. al, and which may be of independent interest.

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Alejandra Brewer Castano, Jessica McDonald, Kathryn Nurse. 2023-06-07. Group connectivity of 3-edge-connected signed graphs. https://arxiv.org/abs/2306.04151

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