ThmDex – An index of mathematical definitions, results, and conjectures.
Set of symbols
Alphabet
Deduction system
Theory
Zermelo-Fraenkel set theory
Set
Collection of sets
Set union
Successor set
Inductive set
Set of inductive sets
Set of natural numbers
Set of integers
Set of rational numbers
Rational number
P-adic rational number
Definition D5468
Triadic rational number
Formulation 0
A D994: Rational number $q \in \mathbb{Q}$ is a triadic rational number if and only if \begin{equation} \exists \, n \in \mathbb{Z}, \, m \in \mathbb{N} : q = \frac{n}{3^m} \end{equation}