Defining matroids through sequential selection
نویسندگان
چکیده
منابع مشابه
Defining matroids through sequential selection
Let E be a finite set and S be a collection of subsets of E . For each x ∈ E let Sx = {S ∈ S | x ∈ S}. Suppose we choose elements x1, . . . , xn in such a way that we first choose x1 belonging to some set of Sx1 . For i = 2, . . . , n we choose xi belonging to some set of Sxi \(Sx1∪· · ·∪Sxi−1 ). We call the set {x1, . . . , xn} a sequential transversal of S , and we let TS be the set of all se...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2007
ISSN: 0195-6698
DOI: 10.1016/j.ejc.2004.11.006