Hello.(adsbygoogle = window.adsbygoogle || []).push({});

I have been reading a book with an introductory section on number theory and the part regarding Euler's function just said that [tex] \varphi (n) = n-1 [/tex] when n is prime and that [tex] \varphi (n) = n(1-\frac{1}{p_{1}})(1-\frac{1}{p_{2}})...(1-\frac{1}{p_{n}}) [/tex] when n is a composite number.

The book (What is mathematics by Richard Courant) said the proof was "completely trivial" but that they wouldn't say it and I was wondering if someone could provide a proof or guide me through one.

Thanks in advance.

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Proof of Euler's fuction.

Loading...

Similar Threads - Proof Euler's fuction | Date |
---|---|

A Is the proof of these results correct? | Jan 29, 2018 |

I Doubt about proof on self-adjoint operators. | Nov 11, 2017 |

Euler Totient Property Proof | Jun 28, 2012 |

Question from the proof in euler's forumla | Mar 14, 2011 |

Euler's polynomial proof | May 29, 2009 |

**Physics Forums - The Fusion of Science and Community**