Octadecagon
Octadecagon
An 18-sided polygon, sometimes also called an octakaidecagon.
See also
Polygon, Regular Polygon, Trigonometry Angles--Pi/18Explore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Octadecagon." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Octadecagon.html