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Omega function

In mathematics, omega function refers to a function using the Greek letter omega, written ω or Ω.

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In mathematics, omega function refers to a function using the Greek letter omega, written ω or Ω.

Ω {\displaystyle \Omega } (big omega) may refer to:

  • The lower bound in Big O notation, f Ω ( g ) {\displaystyle f\in \Omega (g)\,\!} , meaning that the function f {\displaystyle f\,\!} dominates g {\displaystyle g\,\!} in some limit
  • The prime omega function Ω ( n ) {\displaystyle \Omega (n)\,\!} , giving the total number of prime factors of n {\displaystyle n\,\!} , counting them with their multiplicity.
  • The Lambert W function Ω ( x ) {\displaystyle \Omega (x)\,\!} , the inverse of y = x e x {\displaystyle y=x\cdot e^{x}\,\!} , also denoted W ( x ) {\displaystyle W(x)\,\!} .
  • Absolute infinity

ω {\displaystyle \omega } (omega) may refer to: