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\title{How to Prove it in Isabelle/HOL}
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\author{Tobias Nipkow}
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\begin{abstract}
How does one perform induction on the length of a list? How are numerals
converted into \isa{Suc} terms? How does one prove equalities in rings
and other algebraic structures?
This document is a collection of practical hints and techniques for dealing
with specific frequently occurring situations in proofs in Isabelle/HOL.
Not arbitrary proofs but proofs that refer to material that is part of
\isa{Main} or \isa{Complex\_Main}.
This is \emph{not} an introduction to
\begin{itemize}
\item proofs in general; for that see mathematics or logic books.
\item Isabelle/HOL and its proof language; for that see the tutorial
\cite{ProgProve} or the reference manual~\cite{IsarRef}.
\item the contents of theory \isa{Main}; for that see the overview
\cite{Main}.
\end{itemize}
\end{abstract}
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