Quant, Math & Computer Science Puzzles for Interview Preparation & Brain Teasing
A collection of ~225 Puzzles with Solutions (classified by difficulty and topic)

Oct 18, 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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