Graph Theory, Lecture 13: Colouring I: Colouring vertices

5-colour theorem (5.1.2) with two proofs, one of them a 1-liner (20:20).
Adapt first proof to yield false proof of 4-colour theorem: where's the error?
Greedy algorithm, colouring number, and degeneracy (from 30:00).
The Sweat Conservation Law in mathematics 47:11.
Brooks's Theorem 5.2.4 with proof (from 48:00).
Covers Chapter 5.1 and most of Chapter 5.2.