olymmath

RU-ALLRUSSIAN 2018 Problem 115

  • Grade 11

On the table, there're 10001000 cards arranged on a circle. On each card, a positive integer was written so that all 10001000 numbers are distinct. First, Vasya selects one of the card, remove it from the circle, and do the following operation: If on the last card taken out was written positive integer kk , count the kthk^{th} clockwise card not removed, from that position, then remove it and repeat the operation. This continues until only one card left on the table. Is it possible that, initially, there's a card AA such that, no matter what other card Vasya selects as first card, the one that left is always card AA ?

Dataset text AI-MO AoPS. Quoted with source.

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

Add a solution

Similar problems

These problems have the most words in common with this statement.

Locator ru-allrussian/2018/p115 · Tag SYBVFE3RTZ · Edit this page on GitHub · Keys: j next, k previous