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PrimeNu ​

The number of distinct prime factors of n.

WikipediaPrime omega functionMathWorldDistinctPrimeFactorsWikidataQ55630466DLMF27.2.i.p1OEISA001221Wolfram LanguagePrimeNu✓
PrimeNu(n)number of distinct prime factors of .

Domain: Number theory

Details
  • Counts distinct primes only -- , not 5.
  • Equal to the length of FactorInteger.
  • : 1 has no prime factors.
  • Always , with equality exactly when is squarefree. See PrimeOmega.

Examples

See also: PrimeOmega, FactorInteger