\begin{theindex} 
 \makeatletter\scan@allowedfalse
{\bfseries\hfil N\hfil}\nopagebreak

  \item \verb*+\newfloat+\pfill \usage{1}

  \indexspace
{\bfseries\hfil R\hfil}\nopagebreak

  \item \verb*+\restylefloat+\pfill \usage{1}

 \end{theindex}