A

**string**

*over*$\mathcal{A}$ is a D63: Finite sequence $\{ 1, \ldots, N \} \to \mathcal{A}$.

Formulation 0

Let $\mathcal{A}$ be an D221: Alphabet.

A**string** *over* $\mathcal{A}$ is a D63: Finite sequence $\{ 1, \ldots, N \} \to \mathcal{A}$.

A

Also known as

Word, Expression