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arXiv · 2510.01716

Nowhere-zero 5-flow on signed ladders

Leila Parsaei-Majd
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Abstract

In 1983, Bouchet conjectured that every flow-admissible signed graph admits a nowhere-zero $6$-flow. In this paper, we prove that Bouchet's conjecture holds for all signed ladders, circular and Möbius ladders. In fact, all signed ladders, circular and Möbius ladders admit a nowhere-zero $5$-flow except for one case of signed circular ladders. Of course, the exception also has a nowhere-zero $6$-flow.

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Leila Parsaei-Majd. 2025-10-02. Nowhere-zero 5-flow on signed ladders. https://arxiv.org/abs/2510.01716

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