A Note on Hadwiger’s Conjecture
نویسنده
چکیده
Hadwiger’s Conjecture [7] states that every Kt+1-minor-free graph is t-colourable. It is widely considered to be one of the most important conjectures in graph theory; see [21] for a survey. If every Kt+1-minor-free graph has minimum degree at most δ, then every Kt+1minor-free graph is (δ+1)-colourable by a minimum-degree-greedy algorithm. The purpose of this note is to prove a slightly better upper bound.
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