An Erd os-Gallai Theorem For Matroids
نویسنده
چکیده
Erd os and Gallai showed that for any simple graph with n vertices and circumference c it holds that |E(G)| ≤ 2 (n−1)c.We extend this theorem to simple binary matroids having no F7-minor by showing that for such a matroid M with circumference c(M)≥ 3 it holds that |E(M)| ≤ 1 2 r(M)c(M). Mathematics Subject Classi cation (2000). Primary 05D15; Secondary 05B35.
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تاریخ انتشار 2009