Avi has managed to demonstrate that this is probably the correct ANSWER but we still don't have a good derivation, just simulations. I have self-nerd-sniped in a serious way.https://twitter.com/avibryant/status/986057928317648896 …
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
So the true expectation should, I think, be *slightly* lower than this. (Which does seem like it might be true in the simulation results, but that could also just be noise.)
Yeah, that's an interesting question.
I think you're correct. It asymptotically approaches the series for large N as the chance of multiple hits goes down.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.