[r-t] Cayley graphs of doubles extents

Philip Saddleton pabs at cantab.net
Sat Nov 13 08:30:42 UTC 2004

Alexander Holroyd <holroyd at math.ubc.ca> wrote at 11:54:02 on Fri, 12 Nov
>I don't know how to put it on a truncated icosahedron.  Where are the
>generators?  (Not on the edges of the solid, certainly, since it has
>pentagonal faces...)
>I'm certainly intending to draw stedman, grandsire, plain bob etc (perhaps
>with all the other edges faintly visible).
>One could also make a 3D model.  I suggest making the quadrilateral faces
>(which form 20 hexagonal prisms) out of paper, and leaving the hexagonas
>> Can you put the vertices for the in-course extent on a truncated
>> icosahedron to show the symmetry? And display just the edges that
>> correspond to a particular touch? I'd like to see Stedman like this.

There are also hexagonal faces: one of the generators can be the edges
where two of these meet. Make this 3, and you can place 1 & 5
symmetrically: unfortunately they then cross.

[The attachment to this message is 52,000 bytes.  It can be found at



More information about the ringing-theory mailing list