We prove that any simple planar graph is 5-list-colorable. We also show an example of a planar graph that is 3-colorable but not 4-list-colorable.

References:
N. ROBERTSON, D. P. SANDERS, P. SEYMOUR & R. THOMAS: The four-colour theorem, J. Combinatorial Theory, Ser. B 70 (1997), 2-44.
M. Aigner and G. M. Ziegler, Proofs from THE BOOK, 6th ed., Springer, Berlin, 2018.

0:00 Intro
0:35 Preparation
2:13 6-coloring
4:51 List coloring
6:10 4-list-coloring
7:58 5-list-coloring

Music: MusMus

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