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Timeline for Billiard circuits in pentagons

Current License: CC BY-SA 4.0

16 events
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Sep 2 at 18:42 history edited Oscar Lanzi CC BY-SA 4.0
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Oct 6, 2023 at 11:15 vote accept Joseph O'Rourke
Oct 6, 2023 at 0:53 comment added Oscar Lanzi @JosephO'Rourke maybe this isnit sufficient, though (so I add "am9ng other things"). Some further results with using different side nllengths in Case 2 suggest other criteria must be met.
Oct 6, 2023 at 0:51 history edited Oscar Lanzi CC BY-SA 4.0
added 21 characters in body
Oct 6, 2023 at 0:36 comment added Joseph O'Rourke "the circumcenter of every triangle formed by three adjacent vertices lies inside the pentagon.": A very plausible conjecture.
Oct 6, 2023 at 0:25 history edited Oscar Lanzi CC BY-SA 4.0
Added an angular criterion.
Oct 5, 2023 at 20:27 history edited Oscar Lanzi CC BY-SA 4.0
edited body
Oct 5, 2023 at 14:11 history edited Oscar Lanzi CC BY-SA 4.0
edited body
Oct 5, 2023 at 14:04 history edited Oscar Lanzi CC BY-SA 4.0
Summary sentence.
Oct 5, 2023 at 12:41 comment added Oscar Lanzi I have a proper billiard path now.
Oct 5, 2023 at 12:41 history edited Oscar Lanzi CC BY-SA 4.0
Added a new figure.
Oct 5, 2023 at 11:10 comment added Joseph O'Rourke To answer why the definition: Tabachnikov calls it a "Fagnano" billiard path, analogous to the Fagnano path in a triangle.
Oct 5, 2023 at 10:48 comment added Oscar Lanzi It turns out also that if you didn't require the consecutive order, then quadrilaterals woukd include all rhombi -> not necessarily cyclic. Frankly, I just like this pentagonal pattern!
Oct 5, 2023 at 10:10 comment added Joseph O'Rourke Very nice! But you are right, the definition of billiard circuit requires reflections "from consecutive edges."
Oct 5, 2023 at 1:01 history edited Oscar Lanzi CC BY-SA 4.0
Disagreement over the q!
Oct 5, 2023 at 0:49 history answered Oscar Lanzi CC BY-SA 4.0