Uniqueness quantification

In mathematics and logic, the term "uniqueness" refers to the property of being the one and only object satisfying a certain condition. This sort of quantification is known as uniqueness quantification or unique existential quantification, and is often denoted with the symbols "∃!" or "∃₌₁". For example, the formal statement

${\displaystyle \exists !n\in \mathbb {N} \,(n-2=4)}$

may be read as "there is exactly one natural number ${\displaystyle n}$ such that ${\displaystyle n-2=4}$".