---
tag: E1C53WBJ4M
kind: concept
name: Cayley's mousetrap
aliases: [cayley-mousetrap]
sources:
  - wikipedia: en:9380313@r1258129802
    locator: Cayley's mousetrap
    note: adopted
    mention: wikipedia://en/9380313
    sections: [Summary]
same_as:
  wikidata: Q4726764
  wikipedia: Cayley's mousetrap
inventory: [RS61XNQX53]
---

## Summary

**Mousetrap** is the name of a game introduced by the English mathematician Arthur Cayley. In the game, cards numbered $1$ through $n$ ("say thirteen" in Cayley's original article) are shuffled to place them in some random [[permutation|05RWFKVTJ7]] and are arranged in a circle with their faces up. Then, starting with the first card, the player begins counting $1, 2, 3, ...$ and moving to the next card as the count is incremented. If at any point the player's current count matches the number on the card currently being pointed to, that card is removed from the circle and the player starts all over at $1$ on the next card. If the player ever removes all of the cards from the permutation in this manner, then the player wins. If the player reaches the count $n+1$ and cards still remain, then the game is lost.