MoebiusMu
The Möbius function: 0 if n has a squared prime factor, else (-1)^(number of prime factors).
Wikipedia
Möbius functionMathWorldMoebiusFunctionWikidataQ205243Encyclopedia of MathematicsMöbius_functionDLMF27.2.E12FungrimMoebiusMuOEISA008683Wolfram LanguageMoebiusMu!Details
if has a squared prime factor; otherwise for distinct prime factors. by convention, the empty product. - Underlies Möbius inversion:
for every . is squarefree exactly when . See IsSquareFree. is only defined on positive integers; compute-engine leaves unevaluated.
Examples
See also: FactorInteger, IsSquareFree