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Mathematics

Constructing a Regular Heptadecagon with Straightedge and Compass

Quick fact

In 1796, at age 19, Carl Friedrich Gauss discovered that a regular 17-sided polygon is constructible with a straightedge and compass. He was so proud of this feat that he requested a regular heptadecagon be engraved on his tombstone (the sculptor declined, but the discovery remains a landmark).

Why this is interesting

For over two thousand years, no one could construct a regular 17-sided polygon with just a compass and straightedge. Then, a teenager solved it in a single night—and almost didn't tell anyone.