Logic question requiring axiom of choice

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Predicting Real Numbers

Regarding the above question, the solutions require creating classes of sequences with representative sequences.

How are those sequences constructed?

How is it possible to generate a "list" of the classes and representatives if the sequences are made of real numbers which implies the set of sequences is uncountable?

Thanks in advance for any answers.

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It is adequate for the question to define sequences as functions with domain $\mathbb{N}$. So a sequence of reals is just a function $\mathbb{N}\rightarrow\mathbb{R}$.

You are correct that there are uncountably many of them, but if you accept constructing $\mathbb{R}$ then why should the collection $\mathbb{R}^{\mathbb{N}} = \{f \ : \ f:\mathbb{N}\rightarrow\mathbb{R}\}$ be a problem?

They then go on to define an equivalence relation on $\mathbb{R}^{\mathbb{N}}$ by $f \sim g$ iff $\exists n \forall m >n f(m)=g(m)$ (this is called tail equivalence). They then pick a representative from each class, and this is where choice is used, it wasn't used before.