MathDB
Pegs jumping in holes

Source: 2014 BAMO-8 #2

February 22, 2016
combinatoricsproblemsolvingProofOlympiadB8

Problem Statement

There are nn holes in a circle. The holes are numbered 1,2,31,2,3 and so on to nn. In the beginning, there is a peg in every hole except for hole 11. A peg can jump in either direction over one adjacent peg to an empty hole immediately on the other side. After a peg moves, the peg it jumped over is removed. The puzzle will be solved if all pegs disappear except for one. For example, if n=4n=4 the puzzle can be solved in two jumps: peg 33 jumps peg 44 to hole 11, then peg 22 jumps the peg in 11 to hole 44. (See illustration below, in which black circles indicate pegs and white circles are holes.) http://i.imgur.com/4ggOa8m.png
[*]Can the puzzle be solved for n=5n=5? [*]Can the puzzle be solved for n=2014n=2014?
In each part (a) and (b) either describe a sequence of moves to solve the puzzle or explain why it is impossible to solve the puzzle.