arXiv · 1508.05828
This paper attempts to explain the mystery behind an 18th elephant that appears in many popular legends involving the division of a herd of 17 elephants into groups in the ratio 1/2:1/3:1/9.
V. N. Krishnachandran. 2015-08-16. Mystery of the 18th Elephant Solved. https://arxiv.org/abs/1508.05828
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This is a survey on an old open problem in combinatorics called the unit distance problem, and the field of mathematics around it, called incidence geometry. What do we know about the problem? Why is it difficult? How does it connect with other parts of math?
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