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The size of graphs without nowhere-zero 4-flows

✍ Scribed by Hong-Jian Lai

Publisher
John Wiley and Sons
Year
1995
Tongue
English
Weight
428 KB
Volume
19
Category
Article
ISSN
0364-9024

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✦ Synopsis

Let G be a 2-edge-connected simple graph with order n. We show that if IV(G)l 5 17, then either G has a nowhere-zero 4-flow, or G is contractible to the Petersen graph. We also show that for n large, if I€(G)J L (' 2 17) + 34, then either G has a nonwhere-zero 4-flow, or G can be contracted to the Petersen graph.

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