科研之友
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摘要
We establish the following splitter theorem for graphs and its generalization for matroids: Let G and H be 3-connected simple graphs such that G has an H-minor and k := |V(G)| |V(H)| >= 2. Let n := [k/2] + 1. Then there are pairwise disjoint sets X-1,..,X-n subset of E(G) such that each G/X-i; is a 3-connected graph with an H-minor, each Xi is a singleton set or the edge set of a triangle of G with 3 degree-3 vertices and X-1 U center dot center dot center dot U X-n contains no edge sets of circuits of G other than the Xi's. This result extends previous ones of Whittle (for k = 1, 2) and Costalonga (for k = 3).
- 出版日期2018-3
