William D. JonesLooking for a specific integer sequence, but OEIS search is failing...
"Number of possible directed graphs with 'n' nodes"
I think it's 1, 6, and uhhh... I lost count after that.
I Can't Believe It's Not Zero!0 nodes: 1 graph
1 node: 1 or 2 graphs (do you allow a -> a?)
2 nodes: 3 graphs (disconnected, a->b, b->a)? or more (self-loops allowed)?
@cr1901 self-loops allowed is the easy case IIRC, I think it's in one of Doug McIlroy's papers.