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Homework Statement
If a finite connected graph G has minimal degree k, show there exists a path [tex] x_1, x_2, x_3,..., x_k[/tex] so that [tex]G-{x_1,x_2,...,x_k}[/tex] is still connected
Homework Equations
Minimal degree means every vertex has k or more edges connecting to it
The Attempt at a Solution
I'm pretty much nowhere. I can do by induction that you can remove k vertices without disconnecting G by the following:
You can pare G down to a spanning tree, and then it has a vertex you can remove from the tree (since it has to have a leaf). Remove that, and the tree is still connected, so when you add back the rest of the edges it's still connected. This new graph has minimal degree at least k-1 so there are k-1 other vertices you can remove.
I can't see how to make a path though (I tried a similar induction argument for a path but it's demonstrably false as far as I can tell)