On removable series classes in connected matroids
نویسندگان
چکیده
A series class P of a connected matroid M is removable if M \ P is connected. In this paper, we prove that a connected matroid M with r(M) ≥ 2 has at least r(M) + 1 removable series classes. Further, we obtain certain results from which the following result of Oxley and its graph theoretic version follow: If C is a circuit of a connected matroid M with C 6= M such that M \ x is not connected for all x ∈ C, then C contains at least two nontrivial series classes of M.
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عنوان ژورنال:
- Australasian J. Combinatorics
دوره 40 شماره
صفحات -
تاریخ انتشار 2008