
Expanding and understanding the poison pills riddle - Amaan
http://math.stackexchange.com/questions/64742/expanding-and-understanding-the-poison-pills-riddle
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gus_massa
This link from a comment in the submission is more interesting, because it has
the correct answer with the idea of the proof.

<http://www.jdawiseman.com/papers/easymath/weighing.html>

