This may be a little hand-wavy:(adsbygoogle = window.adsbygoogle || []).push({});

Let [tex]a[/tex] be an ordered, proper-class-sized sequence [tex]a=(a_0,a_1,...,a_{\omega},...,a_{\omega_2},...,a_{\omega_{\omega}},...)[/tex] where [tex]a_i, i\in\mathbb{O}rd[/tex] are, say, 0,...,9. So that if we look only at those [tex]a[/tex] whose expansion on [tex]a_{\omega}[/tex] onwards are 0, we'd get something like the real numbers.

We order these things lexicographically (or antilexicographically, whichever it is that the reals are ordered by, I can never remember). So let X be the class of these things. What is X?

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# What am I describing?

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