Journal of Graph Theory
Journal of Combinatorial Theory Series B - Special issue: dedicated to Professor W. T. Tutte on the occasion of his eightieth birthday
The extremal function for complete minors
Journal of Combinatorial Theory Series B
Graph minors. XVI. excluding a non-planar graph
Journal of Combinatorial Theory Series B
Any 7-Chromatic Graphs Has K 7 Or K 4,4 As A Minor
Combinatorica
Graph Minors. XX. Wagner's conjecture
Journal of Combinatorial Theory Series B - Special issue dedicated to professor W. T. Tutte
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Suppose G is a k-connected graph that does not contain Kk as a minor. What does G look like? This question is motivated by Hadwiger's conjecture (Vierteljahrsschr. Naturforsch. Ges. Zürich 88 (1943) 133) and a deep result of Robertson and Seymour (J. Combin. Theory Ser. B. 89 (2003) 43).It is easy to see that such a graph cannot contain a (k - 1)-clique, but could contain a (k - 2)-clique, as Kk-5 + G', where G' is a 5-connected planar graph, shows. In this paper, however, we will prove that such a graph cannot contain three "nearly" disjoint (k - 2)-cliques. This theorem generalizes some early results by Robertson et al. (Combinatorica 13 (1993) 279) and Kawarabayashi and Toft (Combinatorica (in press)).