![](/files/happy5.png)
Problem Prove or disprove: Let
be a graph with the minimum vertex degree at least 2; that is,
. Then there exists a spanning tree
of
such that for every support vertex
in
if
, then
.
![$ G $](/files/tex/b8e7ad0330f925492bf468b5c379baec88cf1b3d.png)
![$ \delta(G)\geq 2 $](/files/tex/96ae81fb0087a7e4c2537972b978fb0cfb8a7c59.png)
![$ T $](/files/tex/79f55d2e1d83a7726c807a70cbe756713b0437b6.png)
![$ G $](/files/tex/b8e7ad0330f925492bf468b5c379baec88cf1b3d.png)
![$ v $](/files/tex/96cbd9a16c6a5eab03815b093b08f3b2db614e9a.png)
![$ T $](/files/tex/79f55d2e1d83a7726c807a70cbe756713b0437b6.png)
![$ \deg_G(v)\geq 3 $](/files/tex/71888edb7df1a28db99d1bb63045685a6a06f9f0.png)
![$ \deg_T(v)\geq 3 $](/files/tex/8a6e3c2c3e888b71a237fa0f69ab0002188b5fcb.png)
A computer search shows that the claim is true for every graph of order at most 8 and minimum vertex degree at least 2.
Bibliography
* indicates original appearance(s) of problem.