Lehman / s Switching Tutte and Game and a Theorem of Nash - Williams l Jack Edmonds
نویسنده
چکیده
The results c ited in the title are unifi ed by th e following theore m: For a ny matroid M a nd any subse ts Nand K of e le me nts in M , there e xi s t as many as k disjoint subsets of N which span K a nd which spa n each ot he r if and only if the re is no contraction matroid M X A where NnA partitions int o as few as k se ts such th at eac h is independen t in M X A and suc h that at least one of the m does not s pan KnA in M x A.
منابع مشابه
Ore, Berge–Tutte, and Gallai–Edmonds
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