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Viewing Version 2 of 'pigeonhole principle'
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Title of object: pigeonhole principle
Canonical Name: PigeonholePrinciple
Type: Theorem

Created on: 2001-10-25 12:01:30-04
Modified on: 2001-10-25 12:08:14-04

Creator: djao
Modifier: djao
Author: djao

Preamble:

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Content:

For any natural number $n$, there does not exist a bijection between $n$ and a proper subset of $n$.
The name of the theorem is based upon the observation that pigeons will not occupy a pigeonhole that already contains a pigeon, so there is no way to fit $n$ pigeons in fewer than $n$ pigeonholes.