Ack. I knew I'd seen this, but wasn't using the right term. Thank you. On Tue, May 10, 2016 at 5:26 PM, Veit Elser <ve10@cornell.edu> wrote:
https://en.wikipedia.org/wiki/Matchstick_graph
"Harborth graph"
On May 10, 2016, at 5:29 PM, Paul Palmer <paul.allan.palmer@gmail.com> wrote:
(Delurking for my first post.)
A while back I saw a fact posted (on Pat's Blog, if anyone reads it) that said:
104 is the lowest known number of unit line segments that can exist in the plane, 4 touching at every vertex.
I can find this repeated all over the internet, but nothing more about it.
I read it as saying that the smallest 4-valent (quartic) unit distance graph has 104 vertices.
Does that sound correct? Does anyone know where this might have come from?
Thanks. I have enjoyed following the discussions on this list. _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
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