Showing posts from October, 2014

Diminishing Differences Puzzle

Source: Australian Mathematical Society Gazette Puzzle Corner 34

Problem: Begin with n integers x1, . . . , xn around a circle. At each turn, simultaneously replace all of them by the absolute differences

Repeat this process until every number is 0, then stop. Prove that this process always terminates if and only if n is a power of 2.
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