Is Wolfram wrong about unique 3-colorability, or am I just confused?
Solution 1:
Yes, Wolfram is wrong in this case. I just checked the archives of the Journal of Combinatorial Theory (where the erratum to the paper in question is published) and the two top vertices are supposed to be connected by an edge.
I cannot provide a link because it requires a login, and I was able to log in through my university's subscription to the journal.
