English

Nowhere-zero flows in signed series-parallel graphs

Combinatorics 2014-11-10 v1

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.

Keywords

Cite

@article{arxiv.1411.1788,
  title  = {Nowhere-zero flows in signed series-parallel graphs},
  author = {Tomáš Kaiser and Edita Rollová},
  journal= {arXiv preprint arXiv:1411.1788},
  year   = {2014}
}
R2 v1 2026-06-22T06:50:43.195Z