这用tikz
画一个吧,虽然很笨。。
\documentclass{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\node at (0,0){$\begin{array}{rcl}
d & dd & d \\
d & dd & dd \\
d & dd & ddd\\
d & dd & dd \\
d & dd & d
\end{array}$};
\draw (-1,0.65) --++ (-0.2,0) --++ (0,-1.25) --++ (2.2,0);
\end{tikzpicture}
\end{document}
使用 tabularray
宏包:
\documentclass{article}
\usepackage{amsmath}
\usepackage{tabularray}
\begin{document}
\begin{tblr}{
colspec = {cccl},
column{1} = {colsep=2pt},
column{3, 4} = {mode=math},
hline{2} = {1}{solid},
hline{5},
vline{1} = {2-4}{solid}
}
& 1. & p \to q & \mathtt{A} \\
& 2. & p \land r & \mathtt{A} \\
& 3. & p & E_{\land}, 2 \\
& 4. & q & E_{\to}, 1, 3 \\
& 5. & (p\land r) \to q & I_{\to}
\end{tblr}
\end{document}
谢谢!