Initial population.

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diff --git a/src/hyper/pages/PERMAN.ht b/src/hyper/pages/PERMAN.ht
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+% Copyright The Numerical Algorithms Group Limited 1992-94. All rights reserved.
+% !! DO NOT MODIFY THIS FILE BY HAND !! Created by ht.awk.
+\newcommand{\PermanentXmpTitle}{Permanent}
+\newcommand{\PermanentXmpNumber}{9.62}
+%
+% =====================================================================
+\begin{page}{PermanentXmpPage}{9.62 Permanent}
+% =====================================================================
+\beginscroll
+The package \spadtype{Permanent} provides the function
+\spadfunFrom{permanent}{Permanent} for square matrices.
+%-% \HDindex{matrix!permanent of}{PermanentXmpPage}{9.62}{Permanent}
+The \spadfunFrom{permanent}{Permanent} of a square matrix can be computed
+in the same way as the determinant by expansion of minors except that for
+the permanent the sign for each element is \spad{1}, rather than being
+\spad{1} if the row plus column indices is positive and \spad{-1}
+otherwise.
+This function is much more difficult to compute efficiently than the
+\spadfunFrom{determinant}{Matrix}.
+An example of the use of \spadfunFrom{permanent}{Permanent} is the
+calculation of the \eth{\spad{n}} derangement number, defined to be the number
+of different possibilities for \spad{n} couples to dance but never with
+their own spouse.
+\xtc{
+Consider an \spad{n} by \spad{n} matrix with entries \spad{0} on the diagonal and
+\spad{1} elsewhere.
+Think of the rows as one-half of each couple (for example, the males) and the
+columns the other half.
+The permanent of such a matrix gives the desired derangement number.
+}{
+\begin{spadsrc}[\bound{kn}]
+kn n ==
+  r : MATRIX INT := new(n,n,1)
+  for i in 1..n repeat
+    r.i.i := 0
+  r
+\end{spadsrc}
+}
+\xtc{
+Here are some derangement numbers, which you see grow quite fast.
+}{
+\spadpaste{permanent(kn(5) :: SQMATRIX(5,INT)) \free{kn}}
+}
+\xtc{
+}{
+\spadpaste{[permanent(kn(n) :: SQMATRIX(n,INT)) for n in 1..13] \free{kn}}
+}
+\endscroll
+\autobuttons
+\end{page}
+%