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arXiv · 1411.1788

Nowhere-zero flows in signed series-parallel graphs

Tomáš Kaiser·Edita Rollová
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Abstract

Bouchet conjectured in 1983 that each signed graph that admits a nowhere-zero flow has a nowhere-zero 6-flow. We prove that the conjecture is true for all signed series-parallel graphs. Unlike the unsigned case, the restriction to series-parallel graphs is nontrivial; in fact, the result is tight for infinitely many graphs.

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Tomáš Kaiser, Edita Rollová. 2014-11-06. Nowhere-zero flows in signed series-parallel graphs. https://arxiv.org/abs/1411.1788

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