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arXiv · 2604.22501

Cyclically $5$-edge-connected snarks with resistance $2$ and flow resistance $n$

Davide Mattiolo·Pietro Negrini·Silvia M. C. Pagani
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Abstract

Snarks are $2$-connected cubic graphs that do not admit a proper $3$-edge-coloring. For a cubic graph $G$, its resistance $r(G)$ is the minimum number of edges whose removal results in a $3$-edge-colorable graph, while its flow resistance $r_f(G)$ is the minimum number of edges whose removal results in a graph admitting a nowhere-zero $\mathbb{Z}_2 \times \mathbb{Z}_2$-flow. In this paper, we provide an affirmative answer to a question recently posed by Allie, M\'a\v{c}ajov\'a, and \v{S}koviera by constructing a family of cyclically $5$-edge-connected snarks for which the ratio $r_f(G)/r(G)$ is arbitrarily large.

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Davide Mattiolo, Pietro Negrini, Silvia M. C. Pagani. 2026-04-24. Cyclically $5$-edge-connected snarks with resistance $2$ and flow resistance $n$. https://arxiv.org/abs/2604.22501

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