Mathematicians: variables are named using Latin, Greek, Fraktur, Hebrew and Linear B letters in bold, italic, script, sans-serif and serif forms.
Also mathematicians: I need some brackets. Guess I'll use good ol' parentheses again! 😎
Sure, here's an example from the lecture notes of a course I'm taking this semester.
Although I personally refuse to use this notation and use angle brackets instead.
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