1872, Gary (A.), the most famous mathematician in Britain at that time, formally put forward this question to the London Mathematical Society, so the four-color conjecture became a concern of the world mathematical community.
1879, A.B. Kempe (1849 ~ 1922), a British lawyer and mathematician, published a paper and "proved" the four-color theorem.
1890, mathematician J. Heawood (186 1 ~ 1955) published a paper, pointing out the major mistakes in Kemp's article; At the same time, it is pointed out that using Kemp method, it can be proved that the coloring of the map only needs five colors at most, which is only one step away from the four-color conjecture.
1922, American mathematician P. Franklin proved that a map with an area of no more than 25 only needs four colors.
In 1926, Reynolds expanded the number of regions to 27.
1940, Winn is further extended to 35.
In 1970, Ore and Stemple proved that the number of regions does not exceed 39.
1976, American mathematicians Appel and Harken spent 1200 hours on two different computers at the University of Illinois in the United States, made 1000 billion judgments, and finally completed the proof of the four-color theorem.
This is about Wayne. I don't know if it is.