# Definition:Bounded Sequence/Complex

## Definition

Let $\sequence {z_n}$ be a complex sequence.

Then $\sequence {z_n}$ is bounded if and only if:

$\exists m, M \in \R$ such that $\forall i \in \N: \cmod {z_i} \le M$

where $\cmod {z_i}$ denotes the complex modulus of $z_i$.

## Unbounded

$\sequence {z_n}$ is unbounded if and only if it is not bounded.