Notation for Sample Space

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Consider an example of flipping a coin infinitely many times. In class, the following notation was used:

$$\Omega=\{H,T\}^{\mathbb{N}}$$

Although I understand what $\Omega$ is supposed to look like, (infinite numerations of the infinite combinations of Heads and Tails), what is the sense/logic behind this notation?

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For sets $A$ and $B$, the notation $B^A$ is used for the set of functions from $A$ to $B$. (Possible reason for this is that if $A$ and $B$ are finite, then $\mid B^A \mid = \mid B \mid^{\mid A \mid}$, where $|S|$ is the number of elements in set $S$).

A sequence of coin tosses can be regarded as a function from $\mathbb{N}$ to $\{H,T\}$ where $1\mapsto$ first toss, etc.