\mathcal{Pro}
Pro\mathcal{Pro}Pro
\mathbb{Pro}
Pro\mathbb{Pro}Pro
\mathrm{Pro}
Pro\mathrm{Pro}Pro
\dbinom{} {} \large{\sum \limits _{k = 0} ^{n}}
()∑k=0n\dbinom{} {} \large{\sum \limits _{k = 0} ^{n}}()k=0∑n
\begin{aligned} &a \\ b&b \end{aligned}
abb\begin{aligned} &a \\ b&b \end{aligned}bab
\begin{cases} a = 1 \\ b = 0 \end{cases}
{a=1b=0\begin{cases} a = 1 \\ b = 0 \end{cases}{a=1b=0