[r-t] # Extents on N bells

[Chris Poole]

> --On 19 August 2004 10:10 +0100 Chris Poole <poole at maths.ox.ac.uk> wrote:
>
> > Why not map the nodes to edges (and vice versa).
>
> How?  You can't make this work in a one-to-one way - try it.

Hmm... that'll be another exercise for the reader!

I was under the impression that it is difficult to prove whether a
Hamiltonian Cycle exists, but can you count them if you know existence to
start with??

Anyway, I've set my brother on to the problem.  Surely his 3 and a bit
years of graph theory must come in use somewhere!

C.