The Colorful Problem That Has Long Frustrated Mathematicians

One of the great episodes in the history of mathematics began on October 23, 1852. In a letter to Sir William Rowan Hamilton, Augustus De Morgan wrote, “A student of mine asked me today to give him a reason for a fact which I did not know was a fact — and do not yet.” To this day, that “fact” continues to enthrall and challenge scholars. The student was Frederick Guthrie, and the “fact” in…

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