the size of the full set, or
the indexes of subset for which the next we will
Value
The next subset in lexicographic oder.
Details
When it is a natural number, then the program take it as the
size of the full set, and returns the indicator of the first subset,
which is a zero vector of the given length.
If it is zero-one vector, then
it read it as a subset indicator, and returns the indicator of the lexicographic next
subset.