The functionality is similar to the one of
`desing/isnc`, but the returning value
provides more information.
In this procedure it is assumed that the hypersurfaces defined by
equations in F without the last equation have normal crossing, and
only the last equation is tested against the previous ones.
- The same as of `desing/isnc`,
except that there is no optional sixth argument.
- A list of indices to F, the maximal cardinality
lexicographically minimal list of divisors which are not normal
crossing with the hypersurface defined by the last equation in F.