This sounds obviously false to me? Why can’t you have a countably infinite graph where all vertices have degree 2?
Biject the graph to z, drop all odd edges and you get a countably infinite subgraph. The key point is that you’re looking for any subgraph that is complete or edgeless.
Ah! I see.
This sounds obviously false to me? Why can’t you have a countably infinite graph where all vertices have degree 2?
Biject the graph to z, drop all odd edges and you get a countably infinite subgraph. The key point is that you’re looking for any subgraph that is complete or edgeless.
Ah! I see.