Correct an error in the definition of PRF^rho.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>

protocol/protocol.tex

@@ -142,7 +142,6 @@
 \newcommand{\InternalHashK}{\mathsf{k}}
 \newcommand{\InternalHash}{\mathsf{InternalH}}
 \newcommand{\Leading}[1]{\mathtt{Leading}_{#1}}
-\newcommand{\Trailing}[1]{\mathtt{Trailing}_{#1}}
 \newcommand{\ReplacementCharacter}{\textsf{U+FFFD}}
 
 % merkle tree
@@ -281,9 +280,9 @@ functions are independent.
 \begin{bytefield}[bitwidth=0.065em]{512}
         \bitbox{242}{256 bit $\CoinAddressPreRand$} &
         \bitbox{14}{1} &
-        \bitbox{14}{0} &
+        \bitbox{14}{1} &
         \bitbox{14}{$i$} &
-        \bitbox{228}{$\Trailing{253}(\hSig)$}
+        \bitbox{228}{$\Leading{253}(\hSig)$}
 \end{bytefield}
 \end{lrbox}