Sigma Function

In mathematics, by sigma function one can mean one of the following:

  • The sum-of-divisors function σa(n), an arithmetic function
  • Weierstrass sigma function, related to elliptic functions
  • Kronecker's sigma function
  • Rado's sigma function, see busy beaver

See also sigmoid function.

Famous quotes containing the word function:

    “Think of the tools in a tool-box: there is a hammer, pliers, a saw, a screwdriver, a rule, a glue-pot, nails and screws.—The function of words are as diverse as the functions of these objects.”
    —Ludwig Wittgenstein (1889–1951)