Department of Mathematics | College of Arts & Sciences

Here is where you make a mistake, you should take 2, instead you take 3, leaving 20 . Now your friend takes 2, leaving 18. Unfortunately, considering that you are starting from 18 = 13 + 5, you should take 5 to win, but you can take at most 4! If your friend makes another mistake you may still be able to win, but not guaranteed! ................
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