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Is there some accepted notation for a set that is compact?

E.g. I am currently writing "... [blah] is true if for every compact set $A \subset \mathbb{R}^n$ and ...".

I could simplify my writing if there was some notation that meant the set $A$ is compact.

Thank you,

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    $\begingroup$ None that I am aware of, but I hope you are saying “for every compact set $A\subseteq \mathbb{R}^n$” rather than $A\in\mathbb{R}^n$... $\endgroup$ – Arturo Magidin Feb 4 '19 at 0:02
  • $\begingroup$ Yes - thanks for the correction :) $\endgroup$ – aaronsnoswell Feb 4 '19 at 0:53
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$K$ is often used for compact sets, but (to my knowledge) there is no notation that definitively designates a set as compact. If you just said "for every $K \subseteq \mathbb{R}^n...$ the reader could not infer that $K$ is compact.

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  • $\begingroup$ Sometimes typos are just that. Your answer is irrelevant now, after that has been fixed. $\endgroup$ – Asaf Karagila Feb 4 '19 at 8:57
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    $\begingroup$ Thanks for pointing out my typo, but my answer is not irrelevant. It's still true that there is no accepted notation for a set that is compact. $\endgroup$ – kccu Feb 4 '19 at 15:53

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