Re: [igraph] Question on generating connected graphs

[Tamás Nepusz]

> anybody point me out to literature dealing with counting the number of 
> such graphs?

The number of connected labeled undirected graphs with n vertices is given by a 
simple recurrence relation (see 
http://en.wikipedia.org/wiki/Graph_enumeration); the first few items of that 
series is given here:

http://oeis.org/A001187

As for an efficient algorithm to generate all the undirected connected graphs 
of a given size, this paper looks promising (although I cannot access it):

http://www.sciencedirect.com/science/article/pii/0097316579900232

Best,
T.