Function: numtoperm
Section: conversions
C-Name: numtoperm
Prototype: LG
Help: numtoperm(n,k): permutation number k (mod n!) of n letters (n
 C-integer).
Doc: generates the $k$-th permutation (as a row vector of length $n$) of the
 numbers $1$ to $n$. The number $k$ is taken modulo $n!\,$, i.e.~inverse
 function of \tet{permtonum}. The numbering used is the standard lexicographic
 ordering, starting at $0$.
