作者: N. Robertson , P.D. Seymour
关键词: Complement graph 、 Combinatorics 、 Graph power 、 Forbidden graph characterization 、 Discrete mathematics 、 Mathematics 、 Factor-critical graph 、 Graph minor 、 Null graph 、 Graph embedding 、 Graph factorization
摘要: Let G be a graph, and let H subgraph of drawn in surface ?. When can this drawing extended to an embedding the whole ?, up 3-separations? We show that if such extension is impossible, subdivision simple 3-connected graph highly "representative", then one two obstructions present. This lemma for use future paper.