Abstract
We study a framework, which we call a generalized kernel system, introduced by Frank. We prove some integral and fractional packing theorems in this framework which, in particular, imply an improvement over the best known upper bounds on the size of the packing, one due to Gabow and Manu, for packing arborescences from a given root, and another, due to Schrijver, for packing branchings from given root-sets in a digraph.
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Acknowledgments
We thank the referees for suggestions that improved the presentation of this paper. We also thank the partial support received from CNPq (Proc. 551561/2009-2, Proc. 303987/2010-3).
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Leston-Rey, M., Wakabayashi, Y. Packing in generalized kernel systems: a framework that generalizes packing of branchings. Math. Program. 149, 209–251 (2015). https://doi.org/10.1007/s10107-014-0746-4
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DOI: https://doi.org/10.1007/s10107-014-0746-4