You can try any of the following fonts for curly characters: calligraphic, fraktur, blackboard bold.

Here is an example:

\documentclass{article}\usepackage{amsmath}\usepackage{amssymb}\begin{document}$\mathcal{APPLE}$ $\mathfrak{APPLE}$ $\mathbb{APPLE}$ \end{document}

\documentclass{article}

\usepackage{amsmath}

\usepackage{amssymb}

\begin{document}

$\mathcal{APPLE}$

$\mathfrak{APPLE}$

$\mathbb{APPLE}$

\end{document}

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