1June, 976, an important event happened: the "four-color theorem" that puzzled mathematicians 100 years was finally proved. The proof was completed by American mathematicians Appel and Harken in 1200 hours with a high-speed computer. If this process needs manual calculation, it will take hundreds of thousands of years. It's unimaginable!

Discovery of four-color problem

1852, Fernandez, who just graduated from London University, found an interesting phenomenon when coloring the map of Britain: no matter how complicated the map is, it can be distinguished by only four colors, that is to say, coloring with four colors can ensure that no two adjacent areas will have the same color.

Fernandez told his brother Frederick about his discovery, which aroused Frederick's strong interest. He was convinced that this conclusion discovered by his brother was correct and tried to prove it from a mathematical point of view, but all his efforts failed. When encountering a mystery, he had to make a special trip to consult his teacher, Professor Augustus de Morgan, a famous British mathematician. Professor Morgan racked his brains to study the problem, but found nothing. Later, he wrote to Hamilton, a famous mathematician in Dublin, and the "four-color conjecture" was first put forward in mathematical form.

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