LaTeX Spacing

\quad space equal to the current font size (= 18 mu)
\, 3/18 of \quad (= 3 mu)
\: 4/18 of \quad (= 4 mu)
\; 5/18 of \quad (= 5 mu)
\! -3/18 of \quad (= -3 mu)
equivalent of space in normal text (e.g. to preserve it)
\qquad 2x \quad (= 36 mu)

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