‘A’ with a lower-case omega on top

Question

How can I write this in TeX (or LaTeX)?

Also, strictly speaking, this is not part of my question, but has anyone seen notation like this? If so, please answer this question.

Answer 1

\documentclass{article}
\usepackage{accents}

\begin{document}
$\accentset{\omega}{A}$
\end{document}

Answer 2

\usepackage{amsmath}

\overset{\omega}{A}

Never seen such a beast.

Answer 3

You may use \stackrel with some movement magic:

\documentclass{article}

\begin{document}
\[\stackrel{\enskip\omega}{A}\]
\end{document}

with result:

Or if you need it sans serif italic like you've shown:

\documentclass{article}
\begin{document}
\[\stackrel{\,\,\omega}{\textsf{\textit{A}}}\]
\end{document}

A very nice solution would be to use package accents, that prevents you from using any movement magic, als long as you are using math fonts only:

\documentclass{article}
\usepackage{accents}

\begin{document}
Nice:
\[\accentset{\omega}{A}\]
Not so nice:
\[\accentset{\omega}{\textsf{\textit{A}}}\]
\end{document}

Answer 4

You can use \overset like this: $\overset{\omega}{A}$ but the result will not be great (the A is slanted and therefore the centering looks off. I like \operatorname* better, since it doesn't make the A slanted. You can use it like:

\[
  \operatorname*{A}^\omega
\]

The results look like this (\overset above, \operatorname below):

I have never seen the notation before by the way.