% {{{ settings
% vim:set fileencoding=utf8:
\documentclass[10pt]{jarticle}

\usepackage{amsmath}
\usepackage{cprotect}
\usepackage{listings}
\usepackage{moreverb}
\usepackage{url}
\usepackage{bussproofs}
\usepackage[dvipdfmx]{graphicx}

% equation number with section number
\makeatletter
\renewcommand{\theequation}{\arabic{section}-\arabic{equation}}
\@addtoreset{equation}{section}
\makeatother

\setlength{\textwidth}{179mm}
\setlength{\textheight}{251mm}
\setlength{\topmargin}{-2cm}
\setlength{\oddsidemargin}{-1cm}
\setlength{\evensidemargin}{-1cm}

% }}}

\pagenumbering{gobble}

\begin{document}

\title{}
\author{}
\date{}

\begin{prooftree}
    \AxiomC{ $ [A] $ $_{(1)}$}
    \AxiomC{ [$ (A \Rightarrow B) \land (B \Rightarrow C)$] $_{(2)}$ }
    \RightLabel{ $ \land 1 \mathcal{E} $ }
    \UnaryInfC{ $ (A \Rightarrow B) $ }
    \RightLabel{ $ \Rightarrow \mathcal{E} $}
    \BinaryInfC{ $ B $ }

    \AxiomC{ [$ (A \Rightarrow B) \land (B \Rightarrow C)$] $_{(2)}$ }
    \RightLabel{ $ \land 2 \mathcal{E} $ }
    \UnaryInfC{ $ (B \Rightarrow C) $ }

    \RightLabel{ $ \Rightarrow \mathcal{E} $}
    \BinaryInfC{ $ C $ }
    \RightLabel{ $ \Rightarrow \mathcal{I} _{(1)}$}
    \UnaryInfC{ $ A \Rightarrow C $}
    \RightLabel{ $ \Rightarrow \mathcal{I} _{(2)}$}
    \UnaryInfC{ $ ((A \Rightarrow B) \land (B \Rightarrow C)) \Rightarrow (A \Rightarrow C) $}
\end{prooftree}

\end{document}