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Flee Jumping on Number Line

Source: All Russian Olympiad 2015 11.5

December 11, 2015
combinatoricsnumber theoryAll Naturals

Problem Statement

An immortal flea jumps on whole points of the number line, beginning with 00. The length of the first jump is 33, the second 55, the third 99, and so on. The length of kthk^{\text{th}} jump is equal to 2k+12^k + 1. The flea decides whether to jump left or right on its own. Is it possible that sooner or later the flee will have been on every natural point, perhaps having visited some of the points more than once?