operation

Operation

An operation on a set $A$ is an n-ary function $\circ :A^n\to A$ that combines $n$ elements (n-tuple) of $A$ to produce another element of $A$:

$$(x_1,x_2,\dots ,x_n)\mapsto x_1\circ x_2\circ \dots \circ x_n$$

Examples

unary operations: negation $-x$, factorial $x!$, successor function $S(x)=x+1$
binary operations: addition $x+y$, multiplication $x\cdot y$, maximum $\max (x,y)$
ternary operations: conditional operator (if-then-else) $\mathrm{cond}(c,x,y)$