The 1 will come up
Source: German Math. Competition BWM 2002, 2nd round, problem 1
November 19, 2005
inductioncombinatorics proposedcombinatorics
Problem Statement
A pile of cards, numbered with , , ..., , is being shuffled. Afterwards, the following operation is repeatedly performed: If the uppermost card of the pile has the number , then we reverse the order of the uppermost cards.
Prove that, after finitely many executions of this operation, the card with the number will become the uppermost card of the pile.