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:
“The English masses are lovable: they are kind, decent, tolerant, practical and not stupid. The tragedy is that there are too many of them, and that they are aimless, having outgrown the servile functions for which they were encouraged to multiply. One day these huge crowds will have to seize power because there will be nothing else for them to do, and yet they neither demand power nor are ready to make use of it; they will learn only to be bored in a new way.”
—Cyril Connolly (1903–1974)