RESEARCH ARTICLE

Flows in 3-edge-connected bidirected graphs

  • Erling WEI , 1 ,
  • Wenliang TANG 2 ,
  • Xiaofeng WANG 3
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  • 1. Department of Mathematics, Renmin University of China, Beijing 100872, China
  • 2. Department of Mathematics, West Virginia University, Morgantown, WV 26505, USA
  • 3. Department of Mathematics and Actuarial Sciences, Indiana University Northwest, Gary, IN 46408, USA

Received date: 07 Oct 2010

Accepted date: 12 Jan 2011

Published date: 01 Apr 2011

Copyright

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg

Abstract

It was conjectured by A. Bouchet that every bidirected graph which admits a nowhere-zero k-flow admits a nowhere-zero 6-flow. He proved that the conjecture is true when 6 is replaced by 216. O. Zyka improved the result with 6 replaced by 30. R. Xu and C. Q. Zhang showed that the conjecture is true for 6-edge-connected graph, which is further improved by A. Raspaud and X. Zhu for 4-edge-connected graphs. The main result of this paper improves Zyka’s theorem by showing the existence of a nowhere-zero 25-flow for all 3-edge-connected graphs.

Cite this article

Erling WEI , Wenliang TANG , Xiaofeng WANG . Flows in 3-edge-connected bidirected graphs[J]. Frontiers of Mathematics in China, 2011 , 6(2) : 339 -348 . DOI: 10.1007/s11464-011-0111-3

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