I think there is an ambiguity or missing constraint in the graph definition for Problem 781. Five example graphs are given to support F(4)=5, but the last example (below) could have the direction of the top blue loop reversed to get another graph. The resulting graph would not be isomorphic to the given examples since the left and right red edges are distinguishable due to sharing vertices with the incoming and outgoing blue edges respectively.
Is isomorphism not the way to consider distinct graphs for this problem? Or are the directions of the blue edges not taken into account?
Problem 781
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jconsidi
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jaap
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Re: Problem 781
If you reverse the direction of those two blue edges, the graph is the same, cause you are just swapping the location of the two blue edges without changing which nodes they connect. It would be more obvious if the two blue edges were drawn parallel rather than one straight and one curved.
