On mod (2p+1)-orientations of graphs
نویسندگان
چکیده
It is shown that every (2p+ 1) log2(|V (G)|)-edge-connected graph G has a mod (2p+ 1)orientation, and that a (4p+ 1)-regular graph G has a mod (2p+ 1)-orientation if and only if V (G) has a partition (V , V −) such that ∀U ⊆ V (G), |∂G(U)| ≥ (2p+ 1)||U ∩ V | − |U ∩ V −||. These extend former results by Da Silva and Dahad on nowhere zero 3-flows of 5-regular graphs, and by Lai and Zhang on highly connected graphs with nowhere zero 3-flows.
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عنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 99 شماره
صفحات -
تاریخ انتشار 2009