run SPASS and Vampire in SOS mode only if >= 50 facts are passed -- otherwise we are probably minimizing and then it's better if the prover is run only once with a full strategy
\index{model checking example|(}%
\index{lfp@{\texttt{lfp}}!applications of|see{CTL}}
\input{CTL/document/Base.tex}
\input{CTL/document/PDL.tex}
\input{CTL/document/CTL.tex}
\index{model checking example|)}