This definition fails because Q-bar needs to be a subset of Q, but in Q-bar, the...

		isaacg on Dec 22, 2022 \| parent \| context \| favorite \| on: A non-constructive proof of the Four Colour Theore... This definition fails because Q-bar needs to be a subset of Q, but in Q-bar, the graphs T1, S2, and T2 are specified to be the single-edge graphs e1, e2, e3. But single-edge graphs are not in Q.