Talk:Reuleaux polygon

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Engineering Mid‑importance

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A Commons file used on this page or its Wikidata item has been nominated for deletion

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UAE 50 Fil Coin (Front).jpg

Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 17:03, 16 April 2021 (UTC)[reply]

Swapped out for a different coin. —David Eppstein (talk) 18:40, 16 April 2021 (UTC)[reply]

I think there is a useful distinction that we are missing on this page. A Reuleaux polygon can have any number of sides >= 2, but it is only a curve of constant width when the number of sides is odd. The Mathworld entry for Reuleaux polygon implies this. I will try to find some better references than those we have already. The article about the 2016 £1 coin is particularly feeble I thought. Thruston (talk) 17:01, 27 December 2021 (UTC)[reply]

Where do you center the arcs for a polygon with an even number of sides, say four sides? It can't be at the opposite vertices because there is no opposite vertex. And if you're just choosing centers and radii arbitrarily, rather than all radii equal and all centers at opposite vertices, then it's an arc-polygon but not a Reuleaux polygon. —David Eppstein (talk) 17:14, 27 December 2021 (UTC)[reply]