A countably infinite number of mathematicians walk into a bar. The first mathematician orders a beer. The second orders half a beer. The third orders one third of a beer. The bartender says "whoa, I'm going to run out of beer!".
A countably infinite number of mathematicians walk into a bar. The first mathematician orders a beer. The second orders half a beer. The third orders one third of a beer. The bartender says "whoa, I'm going to run out of beer!".