ThmDex – An index of mathematical definitions, results, and conjectures.
Set of symbols
Definition D221
Alphabet
Formulation 0
A D3504: Set of symbols $\mathcal{A}$ is an alphabet if and only if
(1) $\mathcal{A}$ is a D2115: Nonempty set
(2) $\mathcal{A}$ is a D17: Finite set
Children
D903: String