Balancing Covectors
نویسندگان
چکیده
Recently, Goddyn, Hochstättler and Hliněný proved that the oriented flow number introduced by Goddy, Tarsi and Zhang for an oriented matroid of rank r is bounded by 14r2 ln r. We improve this bound by showing that any oriented matroid without a coloop admits a reorientation such the imbalance of each covector is at most 3r − 1. In particular this yields a new upper bound for the oriented flow number.
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 25 شماره
صفحات -
تاریخ انتشار 2011