Examples of graphs that are amenable and non-amenable

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The amenable graph $G=(V, E)$ is a graph that satisfies the following

$$ \inf\limits_{K \subset V,\, |K|< \infty} \frac{\partial K}{|K|}=0$$

I know for example that $\mathbb{Z}^2$ is amenable and the Bethe lattice (Cayley tree) is non-amenable.

I am looking for more examples of amenable and non-amenable graphs.

Honeycomb graph, isoradial graph are amenable?

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The honeycomb, the triangular lattice and any other graph with finite isoperimetric dimension is amenable. The most standard examples of the class of non-amenable graphs are rooted regular trees of degree at least $d\ge 2$: take $K$ to be the neighborhood of the root and radius $n$. You have that $|\partial K|$ and $|K|$ have order $d^n$. You could also get the $\mathbb{Z}^d$ and adding edges between any two vertexes to get a non-amenable graph.

Just from those example you can generate a variety of graphs in either class, by noticing that if you have a non-amenable subgraph, your graph is also non-amenable. And that if you "clue" different amenable graphs together, without adding "too many" edges, you will still have a amenable graph.

Another classical way of generating either class of graphs is looking at Caley graphs.

Hope it was useful.