Elementary Set Theory – Notation for Finite Subsets of Natural Numbers

elementary-set-theorynotation

Is there a "standard" notation to denote the set of all finite subsets of $\mathbb{N}$?
(or any set, not just $\mathbb{N}$)

Thanks

Best Answer

Several possible notations for $\{A\subseteq\omega\mid |A|<\omega\}$:

  1. $[\omega]^{<\omega}$
  2. $P_\omega(\omega)$
  3. $\operatorname{Fin}(\omega)$

Where, of course, $\omega=\mathbb N$.

And as usual my advice on the matter: When in doubt, open with "We denote by [the chosen notation here] the set ..."

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