What is...Heawood’s conjecture? скачать в хорошем качестве

What is...Heawood’s conjecture?

Goal. I would like to tell you a bit about my favorite theorems, ideas or concepts in mathematics and why I like them so much. This time. What is...Heawood’s conjecture? Or: I need more than four colors. Disclaimer. Nobody is perfect, and I might have said something silly. If there is any doubt, then please check the references. Slides. http://www.dtubbenhauer.com/youtube.html Mistake. 13:35 I wanted to say: "Where every vertex has exactly five neighbors" - dah! Alternative name. (Franklin-)Ringel-Youngs theorem Material used. https://en.wikipedia.org/wiki/Heawood... https://mathworld.wolfram.com/Heawood... https://en.wikipedia.org/wiki/Heawood... https://oeis.org/A000934 The torus an colorings. https://en.wikipedia.org/wiki/Heawood... https://en.wikipedia.org/wiki/Toroida... The Klein bottle and colorings. https://mathoverflow.net/questions/51... https://en.wikipedia.org/wiki/Frankli... https://mathworld.wolfram.com/Frankli... https://mathworld.wolfram.com/KleinBo... Searching for upper bounds. https://math.stackexchange.com/questi... https://math.stackexchange.com/questi... Four colored maps. https://en.wikipedia.org/wiki/Francis... https://en.wikipedia.org/wiki/Four_co... https://simple.wikipedia.org/wiki/Fou... Mathematica. https://demonstrations.wolfram.com/Ma... https://demonstrations.wolfram.com/Re... https://demonstrations.wolfram.com/Fo... https://demonstrations.wolfram.com/Fo... https://demonstrations.wolfram.com/Fo...