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arXiv · 1809.02907

Alon-Tarsi number of signed planar graphs

Wei Wang·Jianguo Qian
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Abstract

Let $(G,σ)$ be any signed planar graph. We show that the Alon-Tarsi number of $(G,σ)$ is at most 5, generalizing a recent result of Zhu for unsigned case. In addition, if $(G,σ)$ is $2$-colorable then $(G,σ)$ has the Alon-Tarsi number at most 4. We also construct a signed planar graph which is $2$-colorable but not $3$-choosable.

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Wei Wang, Jianguo Qian. 2018-09-09. Alon-Tarsi number of signed planar graphs. https://arxiv.org/abs/1809.02907

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