NZ-flows in strong products of graphs
نویسندگان
چکیده
We prove that the strong product G1 G2 of G1 and G2 is Z3-flow contractible if and only if G1 G2 is not T K2, where T is a tree (we call T K2 a K4-tree). It follows that G1 G2 admits an NZ 3-flow unless G1 G2 is a K4-tree. We also give a constructive proof that yields a polynomial algorithm whose output is an NZ 3-flow if G1 G2 is not a K4-tree, and an NZ 4-flow otherwise. 2009 Wiley Periodicals, Inc. J Graph Theory 64: 267–276, 2010 MSC: 05C15; 05C75; 05C38
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 64 شماره
صفحات -
تاریخ انتشار 2010