Arithmetic Function - Multiplicative and Additive Functions

Multiplicative and Additive Functions

An arithmetic function a is

  • completely additive if a(mn) = a(m) + a(n) for all natural numbers m and n;
  • completely multiplicative if a(mn) = a(m)a(n) for all natural numbers m and n;

Two whole numbers m and n are called coprime if their greatest common divisor is 1; i.e., if there is no prime number that divides both of them.

Then an arithmetic function a is

  • additive if a(mn) = a(m) + a(n) for all coprime natural numbers m and n;
  • multiplicative if a(mn) = a(m)a(n) for all coprime natural numbers m and n.

Read more about this topic:  Arithmetic Function

Famous quotes containing the word functions:

    Let us stop being afraid. Of our own thoughts, our own minds. Of madness, our own or others’. Stop being afraid of the mind itself, its astonishing functions and fandangos, its complications and simplifications, the wonderful operation of its machinery—more wonderful because it is not machinery at all or predictable.
    Kate Millett (b. 1934)