Möbius Function/Examples/6

Example of Möbius Function

For $n \in \Z_{>0}$, let $\map \mu n$ denote the Möbius function of $n$.

Then:

$\map \mu 6 = 1$


Proof

\(\ds 6\) \(=\) \(\ds 2 \times 3\) Prime Decomposition of $6$
\(\ds \leadsto \ \ \) \(\ds \map \mu 6\) \(=\) \(\ds \paren {-1}^2\) as $6$ has $2$ distinct prime divisors
\(\ds \) \(=\) \(\ds 1\)

$\blacksquare$


Sources

  • 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): Möbius function