a new proof of validity of bouchet's conjecture on eulerian bidirected graphs
نویسندگان
چکیده
recently, e. m'{a}v{c}ajov'{a} and m. v{s}koviera proved that every bidirected eulerian graph which admits a nowhere zero flow, admits a nowhere zero $4$-flow. this result shows the validity of bouchet's nowhere zero conjecture for eulerian bidirected graphs. in this paper we prove the same theorem in a different terminology and with a short and simple proof. more precisely, we prove that every eulerian undirected graph which admits a zero-sum flow, admits a zero-sum $4$-flow. as a conclusion we obtain a shorter proof for the previously mentioned result of m'{a}v{c}ajov'{a} and v{s}koviera.
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عنوان ژورنال:
transactions on combinatoricsجلد ۶، شماره ۲، صفحات ۳۱-۳۵
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