The Extremal Function For Noncomplete Minors

@article{Myers2005TheEF,
  title={The Extremal Function For Noncomplete Minors},
  author={Joseph Samuel Myers and Andrew Thomason},
  journal={Combinatorica},
  year={2005},
  volume={25},
  pages={725-753}
}
We investigate the maximum number of edges that a graph G can have if it does not contain a given graph H as a minor (subcontraction). Let $$ c{\left( H \right)} = \inf {\left\{ {c:e{\left( G \right)} \geqslant c{\left| G \right|}{\text{implies}}{\kern 1pt} {\kern 1pt} G \succ H} \right\}}. $$We define a parameter γ(H) of the graph H and show that, if H has t vertices, then $$ c{\left( H \right)} = {\left( {\alpha \gamma {\left( H \right)} + o{\left( 1 \right)}} \right)}t{\sqrt {\log {\kern 1pt… 
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