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Re: Graph
Posted:
Dec 18, 2012 5:12 PM


In article <5d70038296174a00b88f9881a0073257@googlegroups.com>, Sonia <slopezbardo@gmail.com> wrote:
> A planar graph, simple, G with no vertex of degree one or two have a vertex > of degree 3, 4 or 5 > > Do you know how to show, or what book I can find something?
If you have been reading about planar graphs, you have probably seen that if a connected simple planar graph has v vertices and e edges, then e <= 3v  6.
Now suppose your statement is false, i.e. every vertex has degree at least 6. What follows?
Ken Pledger.



