Euler Phi Function of 944

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Example of Use of Euler $\phi$ Function

$\map \phi {944} = 464$

where $\phi$ denotes the Euler $\phi$ Function.


Proof

From Euler Phi Function of Integer:

$\ds \map \phi n = n \prod_{p \mathop \divides n} \paren {1 - \frac 1 p}$

where $p \divides n$ denotes the primes which divide $n$.


We have that:

$944 = 2^4 \times 59$


Thus:

\(\ds \map \phi {944}\) \(=\) \(\ds 944 \paren {1 - \dfrac 1 2} \paren {1 - \dfrac 1 {59} }\)
\(\ds \) \(=\) \(\ds 944 \times \frac 1 2 \times \frac {58} {59}\)
\(\ds \) \(=\) \(\ds 8 \times 58\)
\(\ds \) \(=\) \(\ds 464\)

$\blacksquare$