Given there are $n$ vertex. How to calculate total number of distinct graph having all $n$ vertex. Is there any formula for that?
Sorry one correction here: There is one more rule that there should not be any circular (not finding the correct word) path.
example: If there is one path $v_1 \to v_2 \to v_3$ There should be no path from $v_1 \to v_3$ in the same graph.