Euler Phi Function of 182

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Example of Euler $\phi$ Function of Square-Free Integer

$\map \phi {182} = 72$

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


Proof

From Euler Phi Function of Square-Free Integer:

$\ds \map \phi n = \prod_{\substack {p \mathop \divides n \\ p \mathop > 2} } \paren {p - 1}$

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


We have that:

$182 = 2 \times 7 \times 13$

and so is square-free.


Thus:

\(\ds \map \phi {182}\) \(=\) \(\ds \paren {7 - 1} \paren {13 - 1}\)
\(\ds \) \(=\) \(\ds 6 \times 12\)
\(\ds \) \(=\) \(\ds 72\)

$\blacksquare$