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How many labelled undirected graphs are there with precisely $n$ vertices, $k$ edges, and $t$ triangle subgraphs? (By triangle I mean a graph with three vertices and three edges.)

(Clarification: I am interested only in graphs with no self loops or multiple edges. The graphs do not need to be connected.)

I would appreciate any pointers to results on this problem (exact or approximate). The results I am able to find are typically for unlabelled graphs (e.g. a count up to $n=12$), but in this case I am interested in labelled ones.

I am also interested in possible computational methods for this that are better than brute enumeration.

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I haven't the faintest myself, but in the hope that this leads you somewhere: Cayley's formula for the numbers of labeled trees on $n$ vertices in $n^{n-2}$. – Gyu Eun Lee Jan 21 '13 at 3:11
The number of graphs with $n$ vertices and $k$ edges should be: $n(n-1)/2 \choose k$ – M.M Jul 13 at 9:33
@M.M That's the easy part. Now constrain the triangle count :-) – Szabolcs Jul 13 at 10:34

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