Definition:Ternary Notation

Definition
Ternary numbers are numbers expressed in base $3$ notation.

That is, every number $x \in \R$ is expressed in the form:
 * $\displaystyle x = \sum_{j \mathop \in \Z} r_j 3^j$

where $\forall j \in \Z: r_j \in \left\{{0, 1, 2}\right\}$.