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arXiv · 2603.06747

The degeneracy and Alon-Tarsi number under $F$-sum operations

Zhiguo Li·Zhentao Jiao·Zeling Shao
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Abstract

The Alon-Tarsi number of a graph $ G $ is the smallest $ k $ such that there exists an orientation $ D $ of $ G $ with maximum outdegree $ k - 1 $ satisfying that the number of even Eulerian subgraphs is different from the number of odd Eulerian subgraphs. The degeneracy of a graph $ G $ is the maximum value of the minimum degree over all subgraphs of $ G $. In this paper, we obtain a characterization of graphs with $AT(G)=2$ for any graph $G$, and study the Alon-Tarsi number of $F$-sum in terms of degeneracy.

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Zhiguo Li, Zhentao Jiao, Zeling Shao. 2026-03-06. The degeneracy and Alon-Tarsi number under $F$-sum operations. https://arxiv.org/abs/2603.06747

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