Sequence

A sequence is a list of things, taken in a certain order. $$ \begin{array}{c} (1, 2, 3, -3, 8) \\ (\text{Among, Us, Impostor}) \end{array} $$

Unlike sets, they are instead denoted using brackets instead of braces.

Important features of sequences: ?

• Order of list matters. $(1,2,3)$ and $(3,2,1)$ are different sequences.
• Repeated occurrences matter. $(H,E,L,O)$ and $(H,E,L,L,O)$ are different sequences.