منابع مشابه
Unavoidable minors of graphs of large type
In this paper, we study one measure of complexity of a graph, namely its type. The type of a graph G is deened to be the minimum number n such that there is a sequence of graphs G = G 0 , G 1 , : : : , G n , where G i is obtained by contracting one edge in or deleting one edge from each block of G i?1 , and where G n is edgeless. We show that a 3-connected graph has large type if and only if it...
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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 r...
متن کاملUnavoidable doubly connected large graphs
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2002
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(01)00184-4