The successor function, denoted ${\displaystyle \operatorname {succ} }$ , is a unary operator. Its domain and codomain are the natural numbers; its definition is as follows:

$${\displaystyle {\begin{aligned}\operatorname {succ} :\quad &\mathbb {N} \rightarrow \mathbb {N} \\&n\mapsto (n+1)\end{aligned}}}$$

 

In some programming languages such as C, executing this operation is denoted by postfixing ++ to the operand, i.e. the use of n++ is equivalent to executing the assignment ${\displaystyle n:=\operatorname {succ} (n)}$ .

Many of the elementary functions are unary functions, including the trigonometric functions, logarithm with a specified base, exponentiation to a particular power or base, and hyperbolic functions.

• Arity
• Binary function
• Binary operator
• Ternary operation
• Unary operation

• Foundations of Genetic Programming