Puzzle thread? Puzzle thread.

[DuB]

Just looked at Nelzi's farmer solution. I didn't check the exact figures but it appears to be basically the same idea that I elaborated. I guess you won't be surprised to hear that I think it's missing some rather important details, but then maybe I am just overly verbose . Maybe I'm missing something but I don't see how Nelzi's coin solution does the trick. It clearly works in expectation -- that is, the most likely number of heads remaining on the floor after you pick up half of the coins is 1/2 of the original total -- and likewise the most likely number of heads on the table after you flip that half of the coins is again 1/2 of the total -- but for any one particular attempt there is no guarantee that the two numbers of heads will be equal. In fact, if the total number of coins is large, the strategy will very rarely work on any given attempt. My feeling right now is that anything involving flipping the coins is not going to be a good way to go, because it introduces additional uncertainty into the situation. But I'll think on it some more. Edit: I see that reci hit on one of my ideas for the farmer solution as well.