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\begin{document}

\title{Chapter 3}

\author{}

\date{}

\maketitle

\textbf{1.} 

\begin{verbatim}
paGen <- function(ngen)                                                             
{                                                                                   
   adj <- rbind(0:1,1:0)                                                            
   nverts <- 2  # number of vertices
   for (gen in 1:ngen) {
      # find degrees, normalize to sum to 1
      # ...
      target <- sample(1:nverts,1,prob=degs)
      # form updated/expanded adj matrix   
      # ...
   }                                                                                
   adj 
}                                                                
\end{verbatim}

\end{document}