[seqfan] How many configurations with n dots ?

[michel.marcus at free.fr]

Dear SeqFans, 

These past days I have been trying a game named Shot on Android. 
You can look at a video about it at https://www.youtube.com/watch?v=PE-bEcVnB34 
There one can sees examples of starting configurations with 2 to 5 dots. 
In the game itself, there are some starting positions with up to 11 dots. 
I was wondering if one could build the sequence of the number of possible such configurations and what would the best way to do this. 
For n=2, could we say there is only 1 such position. And for n=3, only 2 or more ? And then how many for higher n ? 

Best. 
Michel.