Unavoidable minors of large 4 - connected
نویسندگان
چکیده
11 It is known that any 3-connected matroid that is large enough is certain to contain 12 a minor of a given size belonging one of a few special classes of matroids. This 13 paper proves a similar unavoidable minor result for large 4-connected bicircular 14 matroids. The main result follows from establishing the list of unavoidable minors 15 of large 4-biconnected graphs, which are the graphs representing the 4-connected 16 bicircular matroids. This paper also gives similar results for internally 4-connected 17 and vertically 4-connected bicircular matroids. 18
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تاریخ انتشار 2013