Name of non-complete graph with certain properties
Is there a name for a graph with the following criteria?
- not a complete graph
- has at least
nvertices (let's sayn > 3to exclude trivial cases) - where every vertex's degree is at least
n.
Or, is there a class of graphs that tend to have this kind of pattern? I've run into graphs like this in my research, and I'm hoping to tap into a body of existing knowledge on them.
$\endgroup$ 31 Answer
$\begingroup$The second condition is redundant given the third: if every vertex has degree $n$, there must be at least $n+1$ vertices.
I would call graphs with the third condition "graphs with minimum degree at least $n$" or "graphs $G$ with $\delta(G) \ge n$". This is concise enough that no further terminology has developed.
There isn't a nice way to exclude the complete graph. You could say "other than complete graphs", but first double-check that whatever you're saying isn't also true for complete graphs, just in case. I guess you could also say "graphs $G$ with $n \le \delta(G) \le |V(G)|-2$", since complete graphs are distinguished by having $\delta(G)=|V(G)|-1$.
If you're looking for properties of such graphs, you should look for properties of graphs with minimum degree at least $n$; excluding complete graphs probably won't get you any more properties beyond that.
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