Closed-form expression
= Closed-form expression
= Closed form
{synonym}
A <mathematical expression> given by a finite combination of specified operations and standard <functions>, rather than an unevaluated <recurrence relation> or an unbounded procedure. Which <functions> are admitted is part of the convention. For example, the <sum> of the first $n$ <positive integers> has the <closed-form expression> $n(n+1)/2$.