MoebiusMu
MoebiusMu[n] gives the Möbius function μ(n).
Examples
Möbius function values:
MoebiusMu[6]
(* 1 *)
MoebiusMu[4]
(* 0 *)
MoebiusMu[30]
(* -1 *)The Möbius function is 0 if n has a squared prime factor.
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