Which is the set for transfinite ordinals $\omega$?

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Let me write down my train of thoughts to make my question clear.

If the collection of elements $\{0,1,2,3,....\}$ is defined as the set $\mathbb{N}$. Then if $\omega$ is the first transfinite ordinal. Is there a corresponding definition (set) for the following collection of elements:

$\{\omega, \omega +1, \omega +2, ...\}$

And/or

$\{0,1,2,...,\omega, \omega +1, \omega +2, ...\}$

And/or

$\{\omega, \omega +1, \omega +2, ..., \omega^2, \omega^2 +1, \omega^2 +2, ..., \omega^3, \omega^3 +1, \omega^3 +2, ..., \omega^{\omega}\}$

And/or

$\{0,1,2,..., \omega, \omega +1, \omega +2, ..., \omega^2, \omega^2 +1, \omega^2 +2, ..., \omega^3, \omega^3 +1, \omega^3 +2, ..., \omega^{\omega}\}$ ?

P.S. If you can write down your sources I would deeply appreciate it

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In the usual development of set theory, each ordinal is represented as the set of all smaller ordinals. (In particular, this makes $\omega$ a name for the set more elementarily known as $\mathbb N$). Therefore, the set $$\{0,1,2,...,\omega, \omega +1, \omega +2, ...\}$$ is the ordinal $\omega\cdot 2$, also known as $\omega+\omega$.

The best notation for $$ \{\omega, \omega +1, \omega +2, ...\}$$ would be $\omega\cdot 2 \setminus \omega$.

The set of all ordinals up to and including $\omega^\omega$ is $\omega^\omega+1$.